How to resolve the replication error 'Remote appliance is not connected, replication remains active'

How to resolve the replication error 'Remote appliance is not connected, replication remains active'

Introduction

This error message means that the replication service on the IBDR Appliance is unable to connect to the replication service on another IBDR Appliance. There are multiple potential root causes for this issue.

Root causes and steps to resolve 

Different firmware version

In case the Primary IBDR Appliance and the Secondary IBDR Appliance are using a different version of the firmware, replication will fail. To resolve this issue, update the IBDR Appliance firmware to the same version on both appliances.
You can find the steps on how to update the firmware on an appliance in the following article:
How to update the firmware on the IBDR Appliance
If the same firmware version is not available on one of the appliances, contact support.

Paired appliance is offline or unreachable

If the paired appliance is not running or unreachable, replication will not run. Ensure that you can access both devices and they are running in normal mode without any issues.

Replication Service is not running on the paired appliance

If Replication Service is stopped on any of the appliances, replication will not be able to communicate with the paired appliance. Ensure that the service is up and running on both devices.

If there is not enough free space on the RAID on the secondary IBDR appliance, replication service will stop automatically to prevent the RAID from reaching maximum capacity. If this occurs, it will be impossible to start the service manually until there is enough free space on the Appliance RAID.

If you need assistance with space management on the appliance, contact support.

Replication Service is stuck in a Stopping or Starting state

Usually, this issue occurs due to a high uptime on the device without rebooting.
You can check the uptime of the device by going to the Appliance Management Console, clicking on the Settings tab, and then looking at the Appliance Status page.
If you are experiencing this issue, please reboot the device.
You can find the steps to reboot the appliance in the following article:
How to reboot an IBDR Appliance via the Management Console

Replication Service ports are blocked

Contact your network team and ensure that the network ports used by the IBDR Appliance replication are whitelisted.
You can find the full list of ports used by the appliance in the following article:
Network ports used by the Backup & Disaster Recovery appliance :: Infrascale Documentation Portal

Replication Configuration mismatch

If the other options have failed to resolve the issue, it is possible that there is a replication configuration mismatch. In order to resolve this, go to the Replication tab of the Appliance Management Console, and then go to the Mode/Options tab. Switch replication to "None", reboot both appliances and configure replication from scratch.