Verifying feature status

For service continuity during ISSU, configure the following feature settings:

Feature

Setting requirements

GR/NSR

Enable GR or NSR for protocols including LDP, RSVP, OSPF, ISIS, BGP, and FSPF.

BFD

Disable BFD for protocols including LDP, RSVP, OSPF, ISIS, RIP, BGP, VRRP, and NQA.

Ethernet link aggregation

Use the long LACP timeout interval (the lacp period short command is not configured) on all member ports in dynamic aggregation groups.

IRF

Configure IRF bridge MAC persistence as follows:

  • Compatible upgrade—Configure the irf mac-address persistent timer or irf mac-address persistent always command.

  • Incompatible upgrade—Configure the irf mac-address persistent always command if the bridge MAC address is the MAC address of the device for which you want to execute the issu load command.

For an ISSU Reboot upgrade on a single-member IRF fabric, also verify that the following features are disabled:

Feature

Remarks

Spanning tree feature

If the spanning tree feature is enabled, service discontinuity might occur during the upgrade because the feature advertises the network topology change.

Dynamic Ethernet link aggregation

During an ISSU reboot, only static aggregation is supported, and dynamic aggregate interfaces might not be able to provide services.

CFD

If CFD is enabled, the CFD CC feature will be disabled during an ISSU reboot, which results in traffic abnormality.

DLDP

If DLDP is enabled, the peer device might consider a link a unidirectional link and shut down the port because it cannot receive probe packets.

Loop detection

If loop detection is enabled, the peer device might enable looped ports because of false loop removal detection.