For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

Serge_M__252_ll's avatar
Serge_M__252_ll
Icon for Nimbostratus rankNimbostratus
Jan 18, 2016

Http::retry after timeout (again)

Hi, this is a reiteration of this question in short the Problem is: i need to retry a Server connection if it takes longer than x to process (eg Server connection died mid request, congestions,...
application delivery
BIG-IP
LTM
Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Jan 19, 2016

Hi Serge,

I do strongly believe, that you have to request your backend systems entirely through SIDEBAND connections, so that you're able to transperently reselect/retry an successfully established - but then somehow stalled server side connection.

The idea behind this approach is, that SIDEBAND connections do provide independend timeouts for the connection establishment (comparable to the LB_FAILED detection) and the received payload (the added functionality you're looking for).

Note1: Using SIDEBANDs to retrieve the content would unfortenately have a strong impact on your performance... 😞

Note2: You may also investigate if your application / web server already supports a configurable maximum response timeout, so that it would send a "503 - Server Busy" response to your your F5 after the given timeout is reached. The 503 response could then be catched during the HTTP_RESPONSE followed by a 

[LB::down]
and 
[HTTP::retry]
.

Cheers, Kai