1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
48 lines
1.6 KiB
Text
48 lines
1.6 KiB
Text
Traffic Shaper For Linux
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This is the current BETA release of the traffic shaper for Linux. It works
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within the following limits:
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o Minimum shaping speed is currently about 9600 baud (it can only
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shape down to 1 byte per clock tick)
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o Maximum is about 256K, it will go above this but get a bit blocky.
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o If you ifconfig the master device that a shaper is attached to down
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then your machine will follow.
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o The shaper must be a module.
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Setup:
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A shaper device is configured using the shapeconfig program.
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Typically you will do something like this
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shapecfg attach shaper0 eth1
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shapecfg speed shaper0 64000
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ifconfig shaper0 myhost netmask 255.255.255.240 broadcast 1.2.3.4.255 up
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route add -net some.network netmask a.b.c.d dev shaper0
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The shaper should have the same IP address as the device it is attached to
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for normal use.
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Gotchas:
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The shaper shapes transmitted traffic. It's rather impossible to
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shape received traffic except at the end (or a router) transmitting it.
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Gated/routed/rwhod/mrouted all see the shaper as an additional device
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and will treat it as such unless patched. Note that for mrouted you can run
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mrouted tunnels via a traffic shaper to control bandwidth usage.
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The shaper is device/route based. This makes it very easy to use
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with any setup BUT less flexible. You may need to use iproute2 to set up
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multiple route tables to get the flexibility.
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There is no "borrowing" or "sharing" scheme. This is a simple
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traffic limiter. We implement Van Jacobson and Sally Floyd's CBQ
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architecture into Linux 2.2. This is the preferred solution. Shaper is
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for simple or back compatible setups.
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Alan
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