Forum Discussion

Sawan_312205's avatar
Sawan_312205
Icon for Nimbostratus rankNimbostratus
Jun 21, 2017

503 service unavailable error

Hi, I have a physical server which sits behind the loadbalancer. When development team generates a load of 100 users on the representing virtual it works fine but later they start getting 503 code ...
application delivery
BIG-IP
LTM
dragonflymr's avatar
dragonflymr
Icon for Cirrostratus rankCirrostratus
Jun 21, 2017

Hi,

 

Not much except checking via tcpdump on internal VLAN if 503 is coming from your backend server, if so then you have performance issue at backend server side.

 

One more thing, if you are using HTTP monitor send string without Connection: close header then it's possible that monitor traffic can create a lot of open TCP connections on the backend server - could be part of the issue.

 

Piotr