It looks like the options in the packets do not march. Any way to get a sniffer on there to see what each is sending as options. It could also be a priority issue if the network is a broadcast/nbma network where neither is being elected a DR? Finally, could a checksum be bad?
-- RFC 1149 Compliant. ""Jenny McLeod"" wrote in message news:200211140127.BAA14210@;groupstudy.com... > OK, I'll admit this is a real-life problem, not strictly a study question. > I have a couple of OSPF adjacencies that refuse to start up. Just to make > this entertaining, these are not router to router - they are Cisco to > mainframe, over a CIP. > Five IP stacks neighbour the router - two are OK, three get stuck in > EXSTART/EXCHANGE. The five IP stacks also connect to a different router, > and these adjacencies are fine. > It looks to me like the classic MTU mismatch symptoms, but a printout of the > m/f definitions shows the MTUs to be 4096, as does "show int" on the > router. I'll get the m/f guru to check the definitions for white space - I > don't know if that will affect it. There have been various m/f changes > lately (and a couple of router ones) errors may have crept into the configs. > > What has me baffled is some of the debug output from the router (debug ip > ospf events). > > Nov 14 11:51:14.121 ESuT: OSPF: Rcv DBD from x.x.x.x on Channel6/0 seq > 0x3DCDF2DA opt 0x2 flag 0x7 len 32 mtu 0 state EXCHANGE > Nov 14 11:51:14.121 ESuT: OSPF: Send DBD to x.x.x.x on Channel6/0 seq > 0x3DCDF2DA opt 0x42 flag 0x2 len 1472 > > The debug doco isn't particularly detailed for this command, but I assume > opt refers to the options field. RFC 2328 seems to think that the first two > bits of the options field should be cleared, so the value of 0x42 being sent > by the router surprises me. > Obviously the value of MTU being reported in the received DBD is also a > concern! > > Other debug output indicates that the m/f sends the same DBD several times > (same seq), which the router acks, then after this is received several times > the router claims > Nov 14 11:51:20.037 ESuT: OSPF: EXCHANGE - OPTIONS/INIT not match > Nov 14 11:51:20.037 ESuT: OSPF: Bad seq received from 92.1.2.20 on Channel6/0 > > Is anyone aware of any other gremlins that cause similar symptoms? Or any > other ideas? > > Thanks, > JMcL Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57413&t=57410 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
