The article helps to resolve a Chassis Cluster 'down' issue, due to the Control Link failing to come up.

This article is part of the Resolution Guide -- SRX Chassis Cluster (High Availability) .

Chassis Cluster is down due to the Control Link being down.

Run the following command to check if the Control Link is down:

Sample output:

For a Branch series SRX services gateway device:

For a High End series SRX services gateway device:

Perform the following steps to troubleshoot and correct a Control Link down:

1. Do you have a switch in between the two Chassis Cluster nodes for the Control Link?

   • Yes - Continue to Step 2
   • No - Go to Step 3

2. Remove the switch and try a direct connection of the control ports. Now reboot the secondary node.

   Are the Control Links still down?
   • Yes – Continue with Step 3
   • No – Is the Chassis Cluster up? - Proceed to KB20641 - [SRX] Troubleshooting steps when the Chassis Cluster does not come up [juniper.net] for analyzing this further

3. Is the interface link light GREEN for control link on both nodes?

   • Yes - Go to Step 5.
   • No -  Continue with Step 4.

4. Change the cable that you are using for control link. Is the interface link light GREEN now?

   • Yes - Previous link cable was faulty. Recommend to now reboot both the nodes simultaneously. Did the control link come up after the reboot? If no, then continue to Step 5
   • No - Go to Step 8 .

5. Is this device an SRX 5000 series service gateway device?

   • Yes - Continue with Step 6.
   • No - Check if you have the correct physical ports connected. Refer to KB15356 - Chassis Cluster Ports Details for SRX Series [juniper.net] for your device.

     Once the correct ports are connected for the control link, if still seeing issue then proceed to Step 7.

6. Reconfigure the control link port to a different SPC, move the cable and reboot both nodes. Is the control link up?

   • Yes - Possible hardware issue with SPC. Continue to Step 8.
   • No - Continue to Step 7.

7. If the Control Link is SFP-type port, change the transceiver on both ends. Ensure that the transceivers are same type (LX, SX, etc.) and that they are Juniper-branded parts. Is the Control Link up now?  

   • Yes - Possible faulty transceiver issue. RMA may be required for the transceivers. Continue to Step 8.
   • No - Continue to Step 8.

8. Follow steps in   KB21781 - [SRX] Data Collection Checklist - Logs/data to collect for troubleshooting [juniper.net] and open a case with your technical support representative.

   Collect the following information for JTAC (collect from both nodes of the Chassis Cluster).

   show chassis cluster status
show chassis cluster statistics
show chassis cluster information
show log jsrpd
show log messages
show log chassisd
request support information

2023-10-18: Minor Modification in the solution section.
2020-09-29: Updated the link in step 5.