Aide Memoires - Maintenance Pages and Cookie Size in IBM HTTP Server / WebSphere Application Server

Saw these on Twitter thanks to IBM_AppServer and thought … hmm, interesting, I may need these two tips at some point down the line.

Configuring a temporary 'Site Down For Maintenance' page in IBM HTTP Server

When IBM HTTP Server is used to front-end a WebSphere Application Server deployment, there might be a need to temporarily redirect users to a 'Site Down For Maintenance' page when one or more back-end Application Servers require off-line maintenance.

Request Header Field Size Exceeds Limit for Web server

Problem(Abstract)

Request to IBM HTTP Server fails with Response code 400.

Symptom

Response from the browser could be shown like this:

Bad Request 
Your browser sent a request that this server could not understand. 
Size of a request header field exceeds server limit. 

IBM HTTP Server Error.log shows the following message:

"request failed: error reading the headers"

Cause

This is normally caused by having a very large Cookie, so a request header field exceeded the limit set for Web Server.

Both have been useful and relevant to me recently, so have shared them here for you, you and you over there.