Figured it out... It was an mtu mismatch ( router e0 mtu 1500, cat vlan15 mtu 1518 ). A "deb ip ospf adj" on r1 revealed the problem. Since changing mtu on lan interface is not possible in IOS...the interface command "ip ospf mtu-ignore" allowed OSPF to deal with the mismatch and just form the adjacency.
The cisco url is: www.cisco.com/warp/public/104/12.pdf Thanks anyway! Dain ""Dain Deutschman"" wrote in message news:[EMAIL PROTECTED] > Hi all, > > I have 3 devices on an ethernet segment where all ethernet interfaces are in > the same vlan and ospf area 0 > > catalyst 3550 priority 0 rid 1.1.1.1 > router5 priority 2 rid 55.55.55.55 BDR > router1 priority 3 rid 11.11.11.11 DR > > The problem is that the switch keeps changing it's state. For example, from > the router 1 perspective I get the following: > ( sh ip ospf nei command ) > > > Neighbor ID Pri State Dead Time Address Interface > 1.1.1.1 0 DOWN/DROTHER - 150.50.15.8 Ethernet0 > 55.55.55.55 2 FULL/BDR 00:00:35 150.50.15.5 Ethernet0 > > Neighbor ID Pri State Dead Time Address Interface > 1.1.1.1 0 EXSTART/DROTHER 00:00:35 150.50.15.8 Ethernet0 > 55.55.55.55 2 FULL/BDR 00:00:38 150.50.15.5 Ethernet0 > > ....and on and on, back and forth etc. > > router 5 perspective: > > > Neighbor ID Pri State Dead Time Address Interface > 1.1.1.1 0 EXSTART/DROTHER 00:00:38 150.50.15.8 > Ethernet0/0 > 11.11.11.11 3 FULL/DR 00:00:30 150.50.15.1 > Ethernet0/0 > > Neighbor ID Pri State Dead Time Address Interface > 1.1.1.1 0 DOWN/DROTHER - 150.50.15.8 > Ethernet0/0 > 11.11.11.11 3 FULL/DR 00:00:32 150.50.15.1 > Ethernet0/0 > > ..switch perspective: > > Neighbor ID Pri State Dead Time Address Interface > 55.55.55.55 2 INIT/DROTHER 00:00:33 150.50.15.5 Vlan15 > 11.11.11.11 3 INIT/DROTHER 00:00:39 150.50.15.1 Vlan15 > > Neighbor ID Pri State Dead Time Address Interface > 55.55.55.55 2 INIT/DROTHER 00:00:37 150.50.15.5 Vlan15 > 11.11.11.11 3 EXCHANGE/DR 00:00:36 150.50.15.1 Vlan15 > > Neighbor ID Pri State Dead Time Address Interface > 55.55.55.55 2 EXCHANGE/BDR 00:00:39 150.50.15.5 Vlan15 > 11.11.11.11 3 EXCHANGE/DR 00:00:39 150.50.15.1 Vlan15 > > So...it seems as though r1 and r5 are recognizing eachother's roles as dr > and bdr correctly. But they see the switch as down or init or exchange > DROTHER. > The switch however, sees itelf as DROTHER and r1/r5 as DROTHER or > init/exchange dr and bdr. Here is the output from "sh ip ospf int vlan15" on > the switch: > > Vlan15 is up, line protocol is up > Internet Address 150.50.15.8/24, Area 0 > Process ID 100, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1 > Transmit Delay is 1 sec, State DROTHER, Priority 0 > No designated router on this network > No backup designated router on this network > Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 > Hello due in 00:00:07 > Index 1/1, flood queue length 0 > Next 0x0(0)/0x0(0) > Last flood scan length is 0, maximum is 0 > Last flood scan time is 0 msec, maximum is 0 msec > Neighbor Count is 2, Adjacent neighbor count is 0 > Suppress hello for 0 neighbor(s) > > Then two seconds later....it changes... > > Vlan15 is up, line protocol is up > Internet Address 150.50.15.8/24, Area 0 > Process ID 100, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1 > Transmit Delay is 1 sec, State DROTHER, Priority 0 > Designated Router (ID) 11.11.11.11, Interface address 150.50.15.1 > Backup Designated router (ID) 55.55.55.55, Interface address 150.50.15.5 > Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 > Hello due in 00:00:05 > Index 1/1, flood queue length 0 > Next 0x0(0)/0x0(0) > Last flood scan length is 0, maximum is 0 > Last flood scan time is 0 msec, maximum is 0 msec > Neighbor Count is 2, Adjacent neighbor count is 0 > Suppress hello for 0 neighbor(s) > > > Any ideas? > > Thanks, > > > -- > Dain Deutschman > CCNP, CSS-1, MCP, CNA > Data Communications Manager > New Star Sales and Service, Inc. > > > > > > > -- > Dain Deutschman > CCNP, CSS-1, MCP, CNA > Data Communications Manager > New Star Sales and Service, Inc. > 800.261.0475 > [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=72877&t=72874 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
