Search code examples
wordpressazureazure-application-gateway

504 Gateway Time-out on Azure App Gateway causing WordPress plugin update errors

We have our WordPress site behind an Azure Application Gateway (WAF v2). When we update WordPress plugins we receive the following error:

Update failed: 504 Gateway Time-out 504 Gateway Time-out Microsoft-Azure-Application-Gateway/v2 
<!-- a padding to disable MSIE and Chrome friendly error page --> 
<!-- a padding to disable MSIE and Chrome friendly error page --> 
<!-- a padding to disable MSIE and Chrome friendly error page --> 
<!-- a padding to disable MSIE and Chrome friendly error page --> 
<!-- a padding to disable MSIE and Chrome friendly error page --> 
<!-- a padding to disable MSIE and Chrome friendly error page -->

Looking in the WAF logs, using the following query, there is no activity when plugins are being updated.

AzureDiagnostics
| where ResourceType == "APPLICATIONGATEWAYS" and Category == "ApplicationGatewayFirewallLog" and action_s != "Allowed"
| project TimeGenerated, hostname_s, requestUri_s, clientIp_s, ruleSetType_s, ruleSetVersion_s, ruleId_s, action_s, Message, instanceId_s

We have set the Request time-out (seconds) to 60 seconds, but this hasn't had any effect. All the above being said the plugins do seem to install, update, and work correctly.

Is there anything we can do to prevent this error?

Solution

  • In the end, I simply increased the Request time-out (seconds) to 120 seconds. After this, every plugin I've installed has installed correctly and without the error.

    This setting can be accessed via:

    1. Application Firewall.
    2. HTTP settings.
    3. Your HTTP settings.
    4. Request time-out (seconds).