790 lines
22 KiB
HTML
790 lines
22 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>( MTU ) - IP MASQ seems to be working fine but some sites don't work.
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This usually happens with WWW and some FTP sites.</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Linux IP Masquerade HOWTO"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Frequently Asked Questions"
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HREF="faq.html"><LINK
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REL="PREVIOUS"
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TITLE="( Odd Behavior ) - When my Internet connection first comes up, nothing
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works. If I try again, everything then works fine. Why is this?"
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HREF="masq-behavior.html"><LINK
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REL="NEXT"
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TITLE="( FTP ) - MASQed FTP clients don't work. "
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HREF="masqed-ftp.html"></HEAD
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><BODY
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CLASS="SECT1"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Linux IP Masquerade HOWTO</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="masq-behavior.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 7. Frequently Asked Questions</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="masqed-ftp.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="SECT1"
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><H1
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CLASS="SECT1"
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><A
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NAME="MTU-ISSUES"
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></A
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>7.15. ( MTU ) - IP MASQ seems to be working fine but some sites don't work.
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This usually happens with WWW and some FTP sites.</H1
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><P
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>Depending on what Linux kernel version you are running on the MASQ server,
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some will people disagree on the real problem. The two following arguments
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have valid points, are inter-related, and users from each camp continue to
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debate this to this day.
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<P
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></P
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><UL
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><LI
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><P
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> With modern 2.4.x Linux systems, most users point their finger at the
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adminstrators of these remote broken sites (typically SSL-encrypted WWW
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sites, etc.) or your MASQ server's upstream router run by your ISP. The
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main though it that these machines are either filtering or not properly
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responding to SOME or ALL FORMS of ICMP packets (specifically ICMP Code 3
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Type 4 - Fragmentation Needed) messages due to a fray of misplaced security
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paranoia.
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</P
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><P
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> What does that all mean? Basically, say your machine is connected to the
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Internet with a MTU of 1492 bytes (Maximum Transmission Unit -- the maximum
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packet size your computer can transmit) which is common for PPPoE users.
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At the same time, the remote WWW/FTP site is connected to the Internet at a
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MTU of 1500 bytes. The way that TCP/IP works is that when a TCP connection
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is being negotiated for your HTTP / FTP connection, the remote side will
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try to verify that a 1500 byte packet can reach your computer via the
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initial TCP "SYN" packet.
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</P
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><P
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> Since the packet is too big for your connection, your upstream router (run
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by your ISP) will send a ICMP 3:4 (fragmentation needed) packet back to the
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remote WWW / FTP server. Within this packet is a recommended smaller MTU
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size to retry with. The problem is that either your local upstream router,
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some router between you and the remote server, or the remote HTTP / FTP
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server is either misconfigured or has a firewall in front of it that is
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BLOCKing these ICMP packets.
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</P
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></LI
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><LI
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><P
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> The final UNCOMMON possibility is a debatable 2.0 / 2.2 kernel bug in the
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IPMASQ code. Some users point their finger to the fact that IPMASQ might
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have problems with ICMP packets that have the DF or "Don't Fragment" bit set.
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Basically, when a MASQ box connects to the Internet with an MTU of anything
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less than 1500, some packets will have the DF field set. Though changing
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the MTU of the MASQ server's Internet link to 1500 seemingly fixes the
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problem, the possible bug is still there. What is believed to be happening
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in these older kernels is that the MASQ code is not properly re-writing the
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return IP addresses of the ICMP 3 Sub 4 code packets back to the originating
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MASQed computer. Because of this, these critical packets get dropped.
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</P
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></LI
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></UL
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></P
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><P
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>No worries though. A there are several perfectly good ways to fix this
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nasty MTU problem:
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<P
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></P
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><UL
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><LI
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><P
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> Enable PMTU clamping in PPPoE
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</P
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><P
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> This solution is mostly for modern 2.4.x and 2.2.x kernel users connected
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to the Internet via a PPPoE DSL or Cablemodem connections. This solution
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allows for changes to be done ONLY on the MASQ server itself and not on all
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of the internal MASQ clients.
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</P
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></LI
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><LI
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><P
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> Enable PMTU clamping via IPTABLES
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</P
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><P
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> This solution is only modern 2.4.x kernel users connected via ANY type
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of Internet connection. This solution allows for changes to be done ONLY on
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the MASQ server itself and not on all of the internal MASQ clients.
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</P
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></LI
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><LI
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><P
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> Change your MASQ server's Internet Link MTU
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</P
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><P
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>This solution will work for any Linux kernel version but is is NOT a
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solution if you have a PPPoE connection for DSL or Cablemodem users.
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</P
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><P
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> It should be noted that some users will balk at this solution because it
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can hurt some latency specific programs like TELNET and Internet games but
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the impact is only slight. On the other hand, most HTTP and FTP traffic
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will SPEED UP!
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</P
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></LI
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><LI
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><P
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> Change the MTU of all internal MASQed machines
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</P
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><P
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> This solution requires the most work as you have to make minor changes to
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ALL of the internal IPMASQed machines. Basically, you would be changing the
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MTU on all of the internal machines to match the MTU of your MASQ server's
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Internet connection. Fortunately, this solution is usually bulletproof
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where as some of the other solutions mentioned in this section might rarely
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not work.
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</P
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></LI
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></UL
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></P
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><DIV
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CLASS="SECT2"
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><H2
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CLASS="SECT2"
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><A
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NAME="AEN2620"
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></A
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>7.15.1. Enabling PMTU Clamping for PPPoE and some PPP Users:</H2
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><P
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> For those users who use PPPoE clients for (DSL / Cablemodem) or PPP (Dialup),
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your Internet connection is NOT "eth0" (for example) but usually "ppp0".
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In addition to this, your Internet link's MTU or Maximum Transmission Unit
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(largest packet you can transmit over the Internet) isn't 1500 bytes but
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1492. The 1492 byte MTU comes from the link size of Ethernet (1518 bytes) -
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Ethernet MAC overhead (18) = 1500. Then you subtract the PPPoE header (8
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bytes) == MTU of 1492. This overhead isn't a big deal but sometimes ISPs or
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remote Internet sites do stupid things to break PPPoE or non-1500 byte MTU
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connected machines.
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</P
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><P
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> You can find more info about this topic on the web. Specifically, here is
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good presentaion on the topic:
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<A
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HREF="http://www.phildev.net/mss/mss-talk.pdf"
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TARGET="_top"
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>mss-talk presentation
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(PDF)</A
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>. Here is the entire
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<A
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HREF="http://www.phildev.net/mss/lisa.html"
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TARGET="_top"
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>Write
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up and other good info</A
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>
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</P
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><P
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> To enable clamping in both the RP or PPPd PPPoE clients, add the following
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line to your /etc/ppp/pppoe.conf file:
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<TABLE
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BORDER="1"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="SCREEN"
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> # - If you have a computer acting as a gateway for a LAN, choose "1412".
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# The setting of 1412 is safe for either setup, but uses slightly more
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# CPU power.
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#
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CLAMPMSS=1412
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</PRE
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></FONT
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></TD
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></TR
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></TABLE
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>
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</P
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></DIV
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><DIV
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CLASS="SECT2"
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><H2
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CLASS="SECT2"
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><A
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NAME="AEN2628"
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></A
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>7.15.2. Clamping the MSS via IPTABLES:</H2
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><P
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> As mentioned above for PPPoE users, some ISPs and WWW sites filter critical
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ICMP packets like MTU Path Discovery. Because of this, many users might find
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more Internet sites work but others hang or work poorly. Fortunately,
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recent IPTABLES have added PMTU Clamping support which should help you. If
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your using IPTABLES and think you're hitting this issue, try adding the
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following line to the end of your rc.firewall-iptables ruleset. It should be noted
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that there is no PMTU clamping support in IPCHAINS.
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<TABLE
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BORDER="1"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="SCREEN"
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> iptables -I FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
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</PRE
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></FONT
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></TD
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></TR
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></TABLE
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>
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</P
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><P
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> If this line causes an error when you re-run the rc.firewall-iptables* firewall
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rulesets, you might need to upgrade your version of IPTABLES which includes
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the "TCPMSS" IPTABLES module.
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</P
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></DIV
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><DIV
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CLASS="SECT2"
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><H2
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CLASS="SECT2"
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><A
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NAME="AEN2633"
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></A
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>7.15.3. Changing the External MTU of the MASQ server:</H2
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><P
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> This solution usually only applies to DIALUP users since PPPoE users cannot
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INCREASE their MTU because of PPPoE's header overhead.</P
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><P
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> To use this solution, first see what your current MTU for your Internet link
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is. To do so, run "/bin/ifconfig" on the MASQ server. Look at the lines
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that corresponds to your Internet connection and look for the MTU (for
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example, ppp0). This NEEDs to be set to 1500. Usually, Ethernet links
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will default to 1500 for Ethernet but serial / DIALUP modem PPP links might
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default to 576.</P
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><P
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><P
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></P
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><UL
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><LI
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><P
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> To change the MTU on a standard Ethernet link to your bridged or routed
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DSL, Cablemodem, etc. connection, you need to edit the correct network
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startup scripts for your Linux distribution. Please see the
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<A
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HREF="http://www.ecst.csuchico.edu/~dranch/LINUX/index-linux.html#TrinityOS"
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TARGET="_top"
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> TrinityOS - Section 16</A
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> document for network optimizations.
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</P
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></LI
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><LI
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><P
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> To change the MTU issue on a PPP (not PPPoE) Internet link, edit your
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"/etc/ppp/options" file and towards the top, add the following text on two
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seperate lines, add:
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<TABLE
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BORDER="1"
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BGCOLOR="#E0E0E0"
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WIDTH="90%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="SCREEN"
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> mtu 1500
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mru 1500
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</PRE
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></FONT
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></TD
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></TR
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></TABLE
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>
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</P
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><P
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> Save these new changes and then restart PPP. Like shown above, verify that
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your PPP link has the correct MTU and MTU.
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</P
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><P
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> CUA Users: Lastly, though this isn't a common problem, some Linux 2.0.x
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kernel users have found a MTU solution to the following problem. With PPP
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users, verify what port is your PPPd code connecting to. Is it a /dev/cua*
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port or a /dev/ttyS* port? It NEEDS to be a /dev/ttyS* port as the
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/dev/cua* device ststem has been deprecated and it breaks some things in
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very odd ways.
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</P
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></LI
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></UL
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></P
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></DIV
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><DIV
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CLASS="SECT2"
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><H2
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CLASS="SECT2"
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><A
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NAME="AEN2647"
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></A
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>7.15.4. Changing the MTU of various operating systems:</H2
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><P
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>If you reconfigure ALL of your MASQed PCs to use the SAME MTU as your external
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Internet link's MTU (for example, 1492 for PPPoE users), everything should
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work fine and this method is sometimes the MOST EFFECTIVE way of fixing things.
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This is including ALL of the solutions mentioned above. But doing things this
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way can be a lot of work if there are lots of internal MASQed machines or be
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even impossible to do if you don't have administrative access to all the
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internal MASQed machines. </P
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><P
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>Follow these simple steps for your respective operating system: </P
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><P
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>The follow examples utilize an MTU of 1492 for typical PPPoE connections for
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some DSL and Cablemodem users. It is recommended to use the HIGHEST values
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possible for all connections that are 128Kb/s and faster.
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It should be noted that some PPPoE ISPs might require an MTU setting of 1460
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(not 1492) for proper connectivity due to additional overhead in the ISP's
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internal network. </P
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><P
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>The only real reason to use smaller MTUs than 1492 or 1460 is to lower your
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Internet link's latency but at the cost of throughput. Please see
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<A
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HREF="http://www.ecst.csuchico.edu/~dranch/PPP/ppp-performance.html#mtu"
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TARGET="_top"
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>http://www.ecst.csuchico.edu/~dranch/PPP/ppp-performance.html#mtu</A
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>
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for more details on this topic.</P
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><P
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>If you know how to make similar changes like these to other
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OSes like OS/2, MacOS, etc. please email <A
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HREF="mailto:dranch@trinnet.net"
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TARGET="_top"
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>David Ranch</A
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> so it can be included in the HOWTO.</P
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><DIV
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CLASS="SECT3"
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><H3
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CLASS="SECT3"
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><A
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NAME="AEN2656"
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></A
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>7.15.4.1. Changing the MTU on Linux:</H3
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><P
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> <TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="PROGRAMLISTING"
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>------------------------------------------
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1. The setting of MTU can vary from Linux distribution to distribution.
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For Redhat: You need to edit the various "ifconfig" statements in
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the /sbin/ifup script
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For Slackware: You need to edit the various "ifconfig" statements in
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the /etc/rc.d/rc1.inet
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2. Here is one good, any-distribution-will-work example, edit the
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/etc/rc.d/rc.local file and put the following at the END of the file:
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echo "Changing the MTU of ETH0"
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/sbin/ifconfig eth0 mtu 1492
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Replace "eth0" with the interface name that is the machine's upstream
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connection which is connected to the Internet.
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3. For advanced options like "TCP Receive Windows" and such, detailed examples
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on how to edit the respective networking scripts for your specific Linux
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distro, etc., please see Chapter 16 of
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http://www.ecst.csuchico.edu/~dranch/LINUX/index-linux.html#trinityos
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------------------------------------------</PRE
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></FONT
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></TD
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></TR
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></TABLE
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> </P
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></DIV
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><DIV
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CLASS="SECT3"
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><H3
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CLASS="SECT3"
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><A
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NAME="AEN2660"
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></A
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>7.15.4.2. Changing the MTU on MS Windows 2000</H3
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><P
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> <TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="PROGRAMLISTING"
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>------------------------------------------
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1. Making ANY changes to the Registry is inheritantly risky but
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with a backup copy, you should be safe. Proceed at your
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OWN RISK.
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2. Goto Start-->Run-->RegEdit
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3. Registry-->Export Registry File-->Save a copy of your registry
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to a reliable place
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4. Navigate down to the key:
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[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Inter
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faces\<ID for Adapter>
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Each ID Adapter has default keys for DNS, TCP/IP address, Default Gateway,
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subnet mask, etc. Find the key one that is for your network card.
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5. Create the following Entry:
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type=DWORD
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name="MTU" (Do NOT include the quotes)
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value=1492 (Decimal) (Do NOT include the text "(Decimal)")
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http://support.microsoft.com/support/kb/articles/Q120/6/42.asp?LN=EN-US&SD=gn&FR=0
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*** If you know how to also change the MSS, TCP Window Size, and the
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*** TTL parameters in NT 2000, please email dranch@trinnet.net as I
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*** would love to add it to the HOWTO.
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5. Reboot to let the changes take effect.
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------------------------------------------</PRE
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></FONT
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></TD
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></TR
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></TABLE
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> </P
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></DIV
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><DIV
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CLASS="SECT3"
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><H3
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CLASS="SECT3"
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><A
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NAME="AEN2664"
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></A
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>7.15.4.3. Changing the MTU on MS Windows NT 4.x</H3
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><P
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><TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="PROGRAMLISTING"
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>------------------------------------------
|
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1. Making ANY changes to the Registry is inheritantly risky but
|
|
with a backup copy, you should be safe. Proceed at your
|
|
OWN RISK.
|
|
|
|
2. Goto Start-->Run-->RegEdit
|
|
|
|
3. Registry-->Export Registry File-->Save a copy of your registry
|
|
to a reliable place
|
|
|
|
4. Create the following keys in the Registry trees, choose two
|
|
possible Registry trees. Multiple entries are for various
|
|
network devices like DialUp Networking (ppp), Ethernet NICs,
|
|
PPTP VPNs, etc.
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|
|
|
http://support.microsoft.com/support/kb/articles/Q102/9/73.asp?LN=EN-US&SD=gn&FR=0
|
|
|
|
|
|
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Parameters\Tcpip]
|
|
and
|
|
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\<Adapter-name>\Parameters\Tcpip]
|
|
|
|
Replace "<Adapter-Name>" with the respective name of your uplink LAN NIC
|
|
interface
|
|
|
|
type=DWORD
|
|
name="MTU" (Do NOT include the quotes)
|
|
value=1492 (Decimal) (Do NOT include the text "(Decimal>")
|
|
|
|
(Do NOT include the quotes)
|
|
|
|
|
|
*** If you know how to also change the MSS, TCP Window Size, and the
|
|
*** TTL parameters in NT 4.x, please email dranch@trinnet.net as I
|
|
*** would love to add it to the HOWTO.
|
|
|
|
5. Reboot to make the changes take effect.
|
|
------------------------------------------</PRE
|
|
></FONT
|
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></TD
|
|
></TR
|
|
></TABLE
|
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></P
|
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></DIV
|
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><DIV
|
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CLASS="SECT3"
|
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><H3
|
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CLASS="SECT3"
|
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><A
|
|
NAME="AEN2668"
|
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></A
|
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>7.15.4.4. Changing the MTU on MS Windows 98:</H3
|
|
><P
|
|
> <TABLE
|
|
BORDER="0"
|
|
BGCOLOR="#E0E0E0"
|
|
WIDTH="100%"
|
|
><TR
|
|
><TD
|
|
><FONT
|
|
COLOR="#000000"
|
|
><PRE
|
|
CLASS="PROGRAMLISTING"
|
|
>------------------------------------------
|
|
1. Making ANY changes to the Registry is inheritantly risky but
|
|
with a backup copy, you should be safe. Proceed at your OWN RISK.
|
|
|
|
2. Goto Start-->Run-->RegEdit
|
|
|
|
3. You should make a backup copy of your Registry before doing anything. To
|
|
do this, copy the "user.dat" and "system.dat" files from the \WINDOWS
|
|
directory and put them into a safe place. It should be noted that the
|
|
previously mentioned method of using "Regedit: Registry-->Export Registry
|
|
File-->Save a copy of your registry" would only perform Registry MERGES
|
|
and NOT do a replacement.
|
|
|
|
4. Search though each of the Registry trees that end in "n" (e.g. 0007)
|
|
and have a Registry entry called "IPAddress" which has the IP address
|
|
of your NIC. Under that key, add the following:
|
|
|
|
From http://support.microsoft.com/support/kb/articles/q158/4/74.asp
|
|
|
|
[Hkey_Local_Machine\System\CurrentControlset\Services\Class\NetTrans\000n]
|
|
type=STRING
|
|
name="MaxMTU" (Do NOT include the quotes)
|
|
value=1492 (Decimal) (Do NOT include the text "(Decimal)")
|
|
|
|
|
|
5. You can also change the "TCP Receive Window" which sometimes
|
|
increases network performance SUBSTANTIALLY. If you notice your
|
|
throughput has DECREASED, put these items BACK to their original
|
|
settings and reboot.
|
|
|
|
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP]
|
|
|
|
type=STRING
|
|
name="DefaultRcvWindow" (Do NOT include the quotes)
|
|
value=32768 (Decimal) (Do NOT include the text "(Decimal>")
|
|
|
|
type=STRING
|
|
name="DefaultTTL" (Do NOT include the quotes)
|
|
value=128 (Decimal) (Do NOT include the text "(Decimal>")
|
|
|
|
|
|
6. Reboot to let the changes take effect.
|
|
------------------------------------------</PRE
|
|
></FONT
|
|
></TD
|
|
></TR
|
|
></TABLE
|
|
> </P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECT3"
|
|
><H3
|
|
CLASS="SECT3"
|
|
><A
|
|
NAME="AEN2672"
|
|
></A
|
|
>7.15.4.5. Changing the MTU on MS Windows 95:</H3
|
|
><P
|
|
> <TABLE
|
|
BORDER="0"
|
|
BGCOLOR="#E0E0E0"
|
|
WIDTH="100%"
|
|
><TR
|
|
><TD
|
|
><FONT
|
|
COLOR="#000000"
|
|
><PRE
|
|
CLASS="PROGRAMLISTING"
|
|
>------------------------------------------
|
|
1. Making ANY changes to the Registry is inheritantly risky but
|
|
with a backup copy, you should be safe. Proceed at your OWN RISK.
|
|
|
|
2. Goto Start-->Run-->RegEdit
|
|
|
|
3. You should make a backup copy of your Registry before continuing. To
|
|
do this, copy the "user.dat" and "system.dat" files from the \WINDOWS
|
|
directory and put them into a safe place. It should be noted that the
|
|
previously mentioned method of using "Regedit: Registry-->Export Registry
|
|
File-->Save a copy of your registry" would only do Registry MERGES and NOT
|
|
do a replacement.
|
|
|
|
4. Search through each of the Registry trees that end in "n" (e.g. 0007)
|
|
and have a Registry entry called "IPAddress", which has the IP address
|
|
of your NIC. Under that key, add the following:
|
|
|
|
From http://support.microsoft.com/support/kb/articles/q158/4/74.asp
|
|
|
|
[Hkey_Local_Machine\System\CurrentControlset\Services\Class\NetTrans\000n]
|
|
|
|
type=DWORD
|
|
name="MaxMTU" (Do NOT include the quotes)
|
|
value=1492 (Decimal) (Do NOT include the text "(Decimal)")
|
|
|
|
type=DWORD
|
|
name="MaxMSS" (Do NOT include the quotes)
|
|
value=1450 (Decimal) (Do NOT include the text "(Decimal>")
|
|
|
|
|
|
5. You can also change the "TCP Receive Window" which sometimes
|
|
increases network performance SUBSTANTIALLY. If you notice your
|
|
throughput has DECREASED, put these items BACK to their original
|
|
settings and reboot.
|
|
|
|
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP]
|
|
type=DWORD
|
|
name="DefaultRcvWindow" (Do NOT include the quotes)
|
|
value=32768 (Decimal) (Do NOT include the text "(Decimal>")
|
|
|
|
type=DWORD
|
|
name="DefaultTTL" (Do NOT include the quotes)
|
|
value=128 (Decimal) (Do NOT include the text "(Decimal>")
|
|
|
|
|
|
6. Reboot to let the changes take effect.
|
|
------------------------------------------</PRE
|
|
></FONT
|
|
></TD
|
|
></TR
|
|
></TABLE
|
|
> </P
|
|
></DIV
|
|
></DIV
|
|
></DIV
|
|
><DIV
|
|
CLASS="NAVFOOTER"
|
|
><HR
|
|
ALIGN="LEFT"
|
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WIDTH="100%"><TABLE
|
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SUMMARY="Footer navigation table"
|
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
|
|
><TD
|
|
WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
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><A
|
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HREF="masq-behavior.html"
|
|
ACCESSKEY="P"
|
|
>Prev</A
|
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></TD
|
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
|
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><A
|
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HREF="index.html"
|
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ACCESSKEY="H"
|
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="masqed-ftp.html"
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ACCESSKEY="N"
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>Next</A
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
|
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>( Odd Behavior ) - When my Internet connection first comes up, nothing
|
|
works. If I try again, everything then works fine. Why is this?</TD
|
|
><TD
|
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WIDTH="34%"
|
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="faq.html"
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ACCESSKEY="U"
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>Up</A
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>( FTP ) - MASQed FTP clients don't work.</TD
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></HTML
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> |