Forum Discussion
wixxyl_98682
Nimbostratus
NimbostratusSyntax on custom health check
All,
Trying to set up basic health check to see if my servers are going down or not. I've built a pool with the appropriate nodes, and applied a health check to them looking for some specific text on the page itself. I don't think I'm doing this correctly, as I cannot make any of the nodes fail checks. So my health check is looking like this.
send string:GET /ews/status.html\r\n
receive string: The emergency system is inactive.The emergency system is inactive.
receive disable string:There is a current emergency.
Where does it look like my issue is. I know it isn't working, I've changed things around on there and it still stays up. I'm not sure of the options on the end of the send string, it was kind of a cut and paste thing from another post. Any help would be appreciated, thanks.
natheCirrocumulus
wixxyl
By default the bigip will use http version 0.9 for monitor strings but I'd recommend a http1.0 or 1.1 request. How about if you try:
GET /ews/status.html HTTP/1.0\r\n\r\n
or..
GET /ews/status.html HTTP/1.1\r\nHost: host.domain.com\r\nConnection: Close\r\n\r\n
BTW, the RFC for http 1.1 requires a host header.
See the following docs for more help:
http://support.f5.com/kb/en-us/solutions/public/2000/100/sol2167.html?sr=23939294 (Constructing HTTP requests for use with the HTTP or HTTPS application health monitor)
http://support.f5.com/kb/en-us/solutions/public/3000/200/sol3224.html?sr=23939294 (HTTP health checks may fail even though the node is responding correctly)
I'd use telnet / curl as well to see if the receive strings are being seen too.
Hope this helps
N