Barracuda Spam Firewall with API firmware 4.1 or later.
Some requests sent via the API, such as the varlist request or the user.list request, may generate a large amount of data as a response. This can cause a timeout when using the XML::RPC module because the XML::RPC module uses a default hard-coded timeout value of 10 seconds in the TreePP.pm module which it depends on.
To fix this you must manually edit your TreePP.pm module within the site_perl/perl_ver/XML folder in your server. A value of at least 120 seconds is recommended, but you may need up to 300 seconds (the default HTTP response timeout for most other operations).
For example, if your Barracuda has over 20,000 users on it and you attempt to get a user.list from the API, it likely that the request will timeout with a 500 READ TIMEOUT from apache. However, after increasing the timeout value from 10 seconds to 120 seconds or more you should get the user list as expected.
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