vSphere Replication 'Not Active' status after initial setup of replication (manually install VIB file)

In my experience this error is caused due to the VIB file not being installed on one or more hosts.

Following the below steps will help you get replication up and running again:

1. Firstly identify which ESXI host the VM resides on that you are attempting to replicate.

2. Download the VIB file for vSphere Replication:

wget https://<vsphere-replication-address>/vib/vr2c-firewall.vib

2. Enable SSH on the ESXI host, scp the file to it:

scp vr2c-firewall.vib root@<esxi-host>/tmp

3. Login to the ESXI host via SSH and install the vib file:

esxcli software vib install -v /tmp/vr2c-firewall.vib

4. Usually the replication should start working immediately - but if it doesn't try restarting the vSphere Replication Appliance.