We might face a scenario of removing a node from existing workflow manager(WFM) farm and add it back during troubleshooting with WFM farm or Service Bus(SB) farm.
In those scenarios, we might lose/forget the Certificate Generation key which is mandatory to be entered while we select the option of "Join to an Existing Workflow Manager Farm". We have also seen engineers rebuilding the farm considering this as a road blocker to join the node back to existing farm.
We need to reset this Certificate Generation Key for WFM and SB separately following below steps.
Reset Certificate Generation Key for WFM using WFM PowerShell:
Note: "WFM$amplepwd1" is the new key we are going to set.
$CertKey=convertto-securestring "WFM$amplepwd1" -asplaintext -force
Set-WFCertificateAutoGenerationKey -WFFarmDBConnectionString 'Data Source=lmc-vsqlp06;Initial Catalog=WFManagementDB;Integrated Security=True;Encrypt=False' -key $CertKey -Verbose
-Update SB CertificateAutoGenerationKey
$mycert=ConvertTo-SecureString -string LMCSharepointProd1 -force -AsPlainText
Set-SBCertificateAutogenerationKey -SBFarmDBConnectionString 'Data Source=lmc-vsqlp06;Initial Catalog=SBManagementDB;Integrated Security=True;Encrypt=False' -key $mycert -Verbose
-Now provide the new Certificate Generation Key (WFM$amplepwd1 in our case) in WFM configuration wizard (and SB configuration wizard) which should accept your new key
-All services started running. To apply the changes, we ran 3 more commands