After setting up ospf over gre over ipsec, I noticed that the neighbours were stuck in "ExStart/DROther" state. This was because I adjusted the MTU only on one tunnel end-point (MTU adjustment is necessary for GRE and IPsec encapsulation).
Code:
quagga-router# sh ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface RXmtL RqstL DBsmL
172.16.0.34 128 Full/DROther 5.573s 172.16.0.41 tun0:172.16.0.42 0 0 0
172.16.0.5 1 ExStart/DROther 4.140s 172.16.0.45 tun1:172.16.0.46 0 0 0
Setting the same MTU value on both GRE endpoints fixed the issue.
After setting up ospf over gre over ipsec, I noticed that the neighbours were stuck in "ExStart/DROther" state. This was because I adjusted the MTU only on one tunnel end-point (MTU adjustment is necessary for GRE and IPsec encapsulation).
[code]quagga-router# sh ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface RXmtL RqstL DBsmL
172.16.0.34 128 Full/DROther 5.573s 172.16.0.41 tun0:172.16.0.42 0 0 0
172.16.0.5 1 ExStart/DROther 4.140s 172.16.0.45 tun1:172.16.0.46 0 0 0
[/code]
Setting the same MTU value on both GRE endpoints fixed the issue.