This article describes the issue of the control link being down, when the SYSIO card is replaced in a SRX1400 chassis cluster.
 

After replacing the SYSIO card in a SRX1400 chassis cluster, it may fail to come up due to the control link being down.

root@SRX1400> show chassis cluster interfaces

Control link status: Down
Control interfaces:
Index Interface Status
0 em0 Down   
1 em1 Down

NOTE: When you use ge-0/0/11 as a control port, you must use a fiber SFP transceiver, but you can use copper or fiber SFP transceiver on ge-0/0/10.

Ports 10 and 11 on the SYSIO card are used as HA control ports, when the chassis cluster mode is enabled. When the devices are not in the cluster mode, these ports can be used as revenue ports. There is a flag stored on the SYSIO card to switch these ports between the HA port and revenue port mode. This flag changes, only when the Chassis Cluster is enabled or disabled.

When installing a new SYSIO card (either received via RMA or from another standalone SRX1400) the port mode flag, which is carried by the new card, will not be reset even after the SRX device is rebooted. The 10 and 11 ports will still be working in the revenue port mode. The devices will not be able to re-join the cluster, as the control link is down. 

 

From the CLI of the node in which the SFB was replaced, enter the following command and reboot the device. This will change the mode of port 10 and 11 on the SYSIO card to chassis cluster mode and the control link will come up after the reboot.

root@SRX1400>set chassis cluster cluster-id <cluster-id> node <node id> reboot

2019-06-09: Content reviewed for accuracy.  Minor grammar changes.