Messages in this thread | | | Date | Tue, 16 Feb 1999 14:05:37 -0500 (EST) | From | "Richard B. Johnson" <> | Subject | Routing Table (Feature) |
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When the startup scripts initialize the network, they generally do `route add -net NNN.NNN.NNN.0 netmask MMM.MMM.MMM.MMM dev DEV` This is for compatibility. Alexy's latest code automatically adds a route when `ifconfig` is executed. This has not caused any problems unless, when a ppp connection is established, you modify the routing table to correspond to the new configuration.
Please don't tell me you don't have to. It depends upon the configuration. My configuration changes the actual network and routes between two networks so I have connectivity between all my home machines and the internet via my ppp link.
In changing the network, from 204.178.40.0, netmask 255.255.248.0 to 204.178.47.0, netmask 255.255.255.0, it is necessary to delete the existing network, i.e., `route del -net 204.178.40.0 netmask 255.255.248.0` and add the new one. Unfortunately, the routing table contains two entries for the same network:
Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 204.178.40.0 * 255.255.248.0 U 0 0 0 eth0 204.178.40.0 * 255.255.248.0 U 0 0 0 eth0 127.0.0.0 * 255.0.0.0 U 0 0 0 lo default cisco.analogic. 0.0.0.0 UG 1 0 0 eth0a
The `ifconfig` command only deletes one. The command has to be executed twice to delete the second one. The problem is that when my ppp link is shut down, I do not add two identical routes back (nor should I). The result is that the second time the ppp link is established, I will get an error if I try to delete two routes. So, a work-around of always deleting two identical routes doesn't work very well.
Therefore, since it has now become the De-facto standard to automatically add routes when the interface is configured, I respectfully ask that when a route is deleted, the kernel software delete all entries of that same route. Since time is not critical, looking through the whole routing table, rather than just exiting when the first equivalent entry is found, will go a long way towards helping to maintain compatibility with existing SYSV systems.
Cheers, Dick Johnson ***** FILE SYSTEM WAS MODIFIED ***** Penguin : Linux version 2.2.1 on an i686 machine (400.59 BogoMips). Warning : It's hard to remain at the trailing edge of technology. Wisdom : It's not a Y2K problem. It's a Y2Day problem.
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