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Bob_10976's avatar
Bob_10976
Icon for Nimbostratus rankNimbostratus
Sep 27, 2010

"Must be Unique" Error messag assigning iRule

Hello all,     Prior to this ASP.Net Vuln issue I had one iRule assigned to all my VIPs which was simply to reject Blank Headers, the code is below. Since then we added a simply redirect to our...
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hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Sep 28, 2010
Hi Bob,

 

 

The error is a result of a restriction enforced in iControl (which the iRuler uses to make changes) but not the GUI. The restriction prevents you from adding an iRule to a VS that already has one or more events of the same priority. This restriction within iControl has been in place going back as far as I know. Priority is used to determine the order of events in iRules being executed. Priorities can range from 1 to 1000 with lower numbers running before higher numbers. By default, if no priority is specified, the event (or all events in the iRule) have a priority of 500.

 

 

For more info on priority, you can check the wiki page:

 

http://devcentral.f5.com/wiki/default.aspx/iRules/priority

 

 

A simple fix for your situation might be to explicitly set the priority of the latest iRule to something other than 500. You should then be able to use the iRuler (or any other iControl app) to add the new iRule to existing virtual servers. Or you could use a command line utility like tmsh or bigpipe to add the iRule(s) to the existing virtual servers. You can check the bigpipe and/or tmsh guides for details.

 

 

Aaron