Intermittent 401 errors

Question

Hello, 
&nbsp;  
&nbsp; I'm getting Intermittent 401 errors. Even when using nodeAddress.exe from the SDK, I get intermittent 401 errors when trying enumerate dips on a BIGIP v9 device. Any ideas what could cause this? It seems to happen 2 out of 10 times. 
&nbsp;  
&nbsp; thanks 
&nbsp; wayne

joe_pruitt · Answer

401 errors indicate a authorization failure from the webserver.  The way most SOAP toolkits work is that they first make the request without the WWW-Authenticate header.  The server will respond with a 401 error and the toolkit will retry with this time passing the credentials in the WWW-Authenticate header. 
&nbsp;  
&nbsp; I've never seen the toolkits report this error out unless the request includes invalid credentials (wrong username or password).  I'm assuming you are using .NET since you referenced the nodeAddress.exe sample in the sdk.  If so, which version of the framework are you using and which version of VS.NET.  I've used up to VS.Net 2005 beta and haven't seen this issue. 
&nbsp;  
&nbsp; Also, are you seeing this on the first connection (first method invocation) or does it randomly happen somewhere within the app? 
&nbsp;  
&nbsp; Can you try to toggle the PreAuthenticate parameter to our proxy class and see if the problem still persists.  If so, then you need to do some more diagnostics on the BIG-IP itself. 
&nbsp;  
&nbsp; Beyond that, this looks to me like it could be a webserver configuration issue on the BIG-IP.  Are you using local or remote authentication on your BIG-IP?  I'm not sure if that could be anything to do with this but it does tie into the authentication process. 
&nbsp;  
&nbsp; The best way to debug this would be to turn on the webserver access logging on the BIG-IP, but I'm not sure if our support department "supports" this. 
&nbsp;  
&nbsp; If none of this helps, I'd suggest you contact BIG-IP customer support and try to get some logging setup on the BIG-IP to track down the issue. 
&nbsp;  
&nbsp; -Joe

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Intermittent 401 errors

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