Reference Guide

Graceful restart
When a networking device restarts, the adjacent neighbors and peers detect the condition. During a graceful restart, the
restarting device and the neighbors continue to forward the packets without interrupting the network performance. The
neighbors that help in the restart process are called as helper routers.
When graceful restart is enabled, the restarting device retains the routes learned by OSPF in the forwarding table. To re
establish OSPF adjacencies with neighbors, the restarting OSPF process sends a grace LSA to all neighbors. In response, the
helper router enters helper mode and sends an acknowledgement back to the restarting device.
OS10 supports graceful restart helper mode. Use the graceful-restart role helper-only command to enable the
helper mode in the ROUTER OSPF mode.
OS10(config)# router ospf 10
OS10(conf-router-ospf-10)# graceful-restart role helper-only
Use the no version of the command to disable the helper mode.
OSPFv2 authentication
You can enable OSPF authentication either with clear text or with MD5.
● Set a clear text authentication scheme on the interface in INTERFACE mode.
ip ospf authentication-key key
● Set MD5 authentication in INTERFACE mode.
ip ospf message-digest-key keyid md5 key
Configure text authentication
OS10(config)# interface ethernet 1/1/1
OS10(conf-if-eth1/1/1)# ip ospf authentication-key sample
View text authentication
OS10(conf-if-eth1/1/1)# show configuration
!
interface ethernet1/1/1
ip address 10.10.10.2/24
no switchport
no shutdown
ip ospf 100 area 0.0.0.0
ip ospf authentication-key sample
Configure MD5 authentication
OS10(config)# interface ethernet 1/1/1
OS10(conf-if-eth1/1/1)# ip ospf message-digest-key 2 md5 sample12345
View MD5 authentication
OS10(conf-if-eth1/1/1)# show configuration
!
interface ethernet1/1/1
ip address 10.10.10.2/24
no switchport
no shutdown
ip ospf 100 area 0.0.0.0
ip ospf message-digest-key 2 md5 sample12345
Troubleshoot OSPFv2
You can troubleshoot the OSPFv2 operations, and check questions for any typical issues that interrupt a process.
● Is OSPF enabled globally?
Layer 3
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