Hi,
By default ACE will do nothing if a real server fails. But you can configure it to send the RST. Below is from user guide:
Configuring the ACE Action when a Server Fails
You can set the action that the ACE takes with respect to connections if any real server fails in a server farm. You can configure the failure action by using the failaction command in either server farm host or server farm redirect configuration mode.
The syntax of this command is as follows:
failaction {purge | reassign}
The keywords and options are as follows:
•purge—Instructs the ACE to remove all connections to a real server if that real server in the server farm fails after you enter this command. The appliance sends a reset (RST) to both the client and the server that failed.
•reassign—Instructs the ACE to reassign the existing server connections to the backup real server (if configured) on the same VLAN interface if the real server fails after you enter this command. If a backup real server has not been configured for the failing server, this keyword has no effect and leaves the existing connections untouched in the failing real server.
More details can be found at :
http://www.cisco.com/c/en/us/td/docs/app_ntwk_services/data_center_app_services/ace_appliances/vA3_1_0/configuration/slb/guide/slbgd/rsfarms.html#wp1117375
Regards,
Kanwal
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