Reset packages

Question

Hello, 
 
 I am running an application with persistent connections behind a UTM. I am having the issue that when a user disconnects from that application for some reason, the UTM does not send a reset package to the service. 
 
 Let me give you an example: 
 A user is VPN in using the UTM. The user is RDP to a server (server receives a SYN package from the UTM). The user disconnects the VPN (or the connection drops). The server still thinks that the user is still connected. Before when we had SonicWall, that wasn't an issue. The SonicWall was sending a RESET package to the server. Please note that the RDP is just an example. 
 
 Is there a way i could ask the UTM to send a reset package to the server? 
 
 Thanks!

sachingurung · Accepted Answer

Any changes in the cc should come after consulting the Support Team. I would suggest you ask your case owner to consult the senior technical team to set a correct value before making that change as it will affect all the TCP connections in general. 
 Thanks

sachingurung · Answer

Hi Vasileiosg, 
 Does deleting the conntrack for the connected IP helps in the disconnection. I think the VPN session will be disconnected but, for some reason the RDP session maintains its conntrack with the UTM. 
 Execute, conntrack -D -s x.x.x.x (system IP from the VPN pool) 
 Thanks

sachingurung · Answer

Hi Vasileiosg, 
 As far as I understand the issue is related to the TIME_WAIT state in the packetfilter timeouts table. After the disconnection of the session, the UTM will wait for a specific time before flushing the connection completely; this is by default 120 seconds. Does changing anything here helps? Be sure to make a change consulting to the senior support engineer. 
 Thanks