230 lines
3.9 KiB
HTML
230 lines
3.9 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>Rules On Bridging</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.63
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"><LINK
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REL="HOME"
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TITLE="Linux BRIDGE-STP-HOWTO"
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HREF="index.html"><LINK
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TITLE="What Is A Bridge?"
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HREF="what-is-a-bridge.html"><LINK
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REL="NEXT"
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TITLE="Preparing The Bridge"
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HREF="preparing-the-bridge.html"></HEAD
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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 BRIDGE-STP-HOWTO: About The Linux Modular Bridge And STP</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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><A
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HREF="what-is-a-bridge.html"
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>Prev</A
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></TD
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HREF="preparing-the-bridge.html"
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>Next</A
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></TD
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></TR
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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="RULES-ON-BRIDGING"
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>4. Rules On Bridging</A
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></H1
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><P
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>There is a number of rules you are not allowed to break
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(otherwise your bridge will do).
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</P
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><P
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></P
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><UL
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COMPACT="COMPACT"
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><LI
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><P
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>A port can only be a member of one bridge.
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</P
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></LI
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><LI
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><P
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>A bridge knows nothing about routes.
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</P
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></LI
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><LI
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><P
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>A bridge knows nothing about higher protocols than <SPAN
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CLASS="ACRONYM"
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>ARP</SPAN
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>.
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That's the reason why it can bridge any possible protocol
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possibly running on your Ethernet.
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</P
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></LI
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><LI
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><P
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>No matter how many ports you have in your logical bridge,
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it's covered by only one logical interface
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</P
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></LI
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><LI
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><P
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>As soon as a port (e.g. a NIC) is added to a bridge you have no
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more direct control about it.
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</P
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></LI
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></UL
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><DIV
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CLASS="WARNING"
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><P
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></P
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><TABLE
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CLASS="WARNING"
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BORDER="1"
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WIDTH="100%"
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><TR
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><TD
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ALIGN="CENTER"
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><B
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>Warning</B
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></TD
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></TR
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><TR
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><TD
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ALIGN="LEFT"
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><P
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>If one of the points mentioned above is not clear to you now,
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don't continue reading.
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Read the documents listed in <A
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HREF="recommended-reading.html"
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>Appendix B</A
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>
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first.
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</P
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></TD
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></TR
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></TABLE
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></DIV
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><P
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>If you ever tried to ping an unmanaged switch, you will know that
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it doesn't work, because you don't have a IP-address for it.
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To switch datagrams it doesn't need one.
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The other thing is if you want to manage the switch.
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It's too much strain, to take a dumb terminal, walk to the
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place you installed it (normally a dark, dusty and warm
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room, with a lot of green and red Christmas lights), to connect the
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terminal and to change the settings.
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</P
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><P
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>What you want is remote management, usually by SNMP, telnet, rlogin
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or (best) ssh.
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For all this services you will need a IP.
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That's the exception to the transparency.
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The new code allows you without any problem to assign a IP address to
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the virtual interface formed by the bridge-instance you will create
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in <A
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HREF="set-up-the-bridge.html#BASIC-SETUP"
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>Section 6.2</A
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>.
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All NIC's (or other interfaces) in your bridge will happily listen and
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respond to datagrams destined to this IP.
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</P
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><P
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>All other data will not interfere with the bridge.
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The bridge just acts like a switch.
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</P
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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WIDTH="100%"
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CELLSPACING="0"
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><TR
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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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><A
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HREF="what-is-a-bridge.html"
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>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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>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="preparing-the-bridge.html"
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>Next</A
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></TD
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></TR
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><TR
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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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>What Is A Bridge?</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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> </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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>Preparing The Bridge</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |