[Xorp-hackers] How to debug OSPF interface migration?

Ben Greear greearb at candelatech.com
Tue Oct 2 18:58:58 PDT 2007


I'm still trying to get interface add/deletion working with OSPF.

First, my initial setup is router '8' connected to router 1 and
router 1 connected to router 2.  These are the only 3 OSPF routers
running.

The router-id is calculated as: 127.1.0.[router-id], for reference.

When I first start the routers, they negotiate up and seem to work
fine.  However, when I migrate the link from 8 - 1 to 8 - 2, it
no longer works.  It seems that router 8 still thinks it is talking
to router 1 (notice the ID that it thinks it is Loading).

I migrate the links with commands like:


# remove interface from router 1
configure
delete protocols ospf4 area 0.0.0.0 interface rddVR44
commit
delete interfaces interface rddVR44
commit
exit
exit


# Add interface to router 2
configure
set interfaces interface rddVR44 vif rddVR44 address 10.4.0.7 prefix-length 24
commit
set protocols ospf4 area 0.0.0.0 interface rddVR44 vif rddVR44 address 10.4.0.7 interface-cost 1
commit
exit
exit

# This 'resets' a port in router 2, in this case it isn't really making changes
# but my code is a bit lazy currently.  I think Xorp is smarter
# doesn't actually do anything.
configure
delete interfaces interface rddVR45 vif rddVR45
set interfaces interface rddVR45 vif rddVR45 address 10.4.0.2 prefix-length 24
commit
delete protocols ospf4 area 0.0.0.0 interface rddVR45 vif rddVR45
set protocols ospf4 area 0.0.0.0 interface rddVR45 vif rddVR45 address 10.4.0.2
commit
exit
exit


When this is complete, it seems router-8 still thinks it is connected to
router 1, but it is really connected to router 2.  According to router 2,
router 8 is in 'Init' mode.

[root at lanforge-33-46 lanforge]# export XORP_FINDER_SERVER_PORT=20008; xorpsh
Welcome to XORP on lanforge-33-46
root at lanforge-33-46> show ospf4 neighbor
   Address         Interface             State      ID              Pri  Dead
10.4.0.7         rddVR45/rddVR45        Loading   127.1.0.1        128    35
root at lanforge-33-46> quit
[root at lanforge-33-46 lanforge]# export XORP_FINDER_SERVER_PORT=20002; xorpsh
Welcome to XORP on lanforge-33-46
root at lanforge-33-46> show ospf4 neighbor
   Address         Interface             State      ID              Pri  Dead
10.0.0.2         rddVR0/rddVR0          Full      127.1.0.1        128    38
10.4.0.2         rddVR44/rddVR44        Init      127.1.0.8        128    38
root at lanforge-33-46> quit
[root at lanforge-33-46 lanforge]# export XORP_FINDER_SERVER_PORT=20001; xorpsh
Welcome to XORP on lanforge-33-46
root at lanforge-33-46> show ospf4 neighbor
   Address         Interface             State      ID              Pri  Dead
10.0.0.1         rddVR1/rddVR1          Full      127.1.0.2        128    31


I'm not to sure how to debug this farther, so please let me know
if you want logs, packet traces, etc.

Thanks,
Ben


-- 
Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com



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