FPCs stuck in present state in chassis cluster.

• FPCs stuck in present state when connecting chassis cluster links (building cluster).

FPCs may get stuck and not come up if the devices are not able to successfully build the cluster, this can occur for multiple reasons:

• Control link not configured (for 5K devices only) or may be not connected on the correct link, please refer to https://www.juniper.net/documentation/us/en/software/junos/chassis-cluster-security-devices/topics/topic-map/security-chassis-cluster-control-plane-interfaces.html to obtain more information on the control link for different platforms.
• Fabric link not configured correctly, please refer to https://www.juniper.net/documentation/us/en/software/junos/chassis-cluster-security-devices/topics/topic-map/security-chassis-cluster-data-plane-interfaces.html
• Configuration mismatch between nodes, for this you can check the number of configuration lines on both nodes using "show | display set | count" from configurational mode, to recover from this state the configuration can be deleted and add only basic chassis cluster configuration such as fabric link, control link, redundancy group 0 configuration, and after this a dual reboot can be performed so that they re-synchronize the configuration.

If the FPCs only get stuck when trying to build the cluster please perform those checks, if it only occurs when the device is on standalone mode then investigate further as it may be something unrelated to chassis cluster configuration.