azure-cliazure-redis-cache

azure cli trigger failover geo-location cache redis


I have created two Premium Azure Cache for Redis resources and set up geo replication. There is a button in the portal to failover manually.

How can I trigger this failover with Azure CLI?

I tried the az redis force-reboot --resource-group $resourceGroupName --name $redisPrimary --reboot-type $rebootType command to no avail.


Solution

  • I did it in PowerShell by breaking the (geo-replication) link between de caches and then re-creating it, making sure to reverse the primary and secondary cache.

    Use the provisioning state to monitor the state after deleting or creating the link:

    $provisioningState = (Get-AzRedisCache -Name $cacheNamePrimary).ProvisioningState
    
    if ($provisioningState -eq 'Succeeded') { etc.. }
    

    One gotcha, after removing the link Remove-AzRedisCacheLink and trying to create a new one New-AzRedisCacheLink, an error might occur even though the provisioning state will report 'Succeeded'. Error message: Operation returned an invalid status code 'Conflict'.

    In this case I created a while loop that breaks when the New-AzRedisCacheLink returns no error:

    # Create cache link (geo-replication)
    while ($true) {
        $provisioningState = (Get-AzRedisCache -Name $cacheNamePrimary).ProvisioningState
    
        if ($provisioningState -eq 'Succeeded') {
            try {
                New-AzRedisCacheLink -PrimaryServerName $cacheNameSecondary -SecondaryServerName $cacheNamePrimary -ErrorAction Stop
                break
            } catch {
                Write-Output "Trying to creating cache link but received an error '$($_)'.. probably busy processing something.. retrying.."
                Start-Sleep -Milliseconds 20000
            }
        } else {
            Start-Sleep -Milliseconds 30000
            Write-Output "Still waiting for cache link to be removed.. provisioning status '$provisioningState'.."
        }
    }