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Date: Wed, 7 Apr 2004 11:38:45 +0200 (CEST)
From: Harti Brandt <harti@cs.tu-berlin.de>
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Subject: interface renaming of an running interface
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Hi all,

I'm currently trying to teach bsnmp to correctly handle interface
renaming. One problem that I encounter is that a process listening on
the routing socket sees an interface departure and an interface arrival
message. This cause interfaces that run stateful protocols like SNMP on
ATM interfaces to drop all connections which isn't really all that nice.
The SNMP daemon would also loose all interface state and would report
the renamed interface as a new interface with a new ifindex. This directly
violates the IF-MIB RFC, because the daemon is required to understand that
this is the same interface (the ifindex doesn't really help here, because
unloading/loading the driver gives the same behaviour). I would like to do
one of the following two things:

1) disallow renaming an interface while it is up, or
2) instead of emiting a departure/arrival pair of routing messages,
generate a rename message.

Additionally I would like to create new sysctls:

net.link.generic.ifdata.<ifindex>.dname
net.link.generic.ifdata.<ifindex>.dunit

to access the driver's name of an interface.

Comments?

harti