Hello I'm reposting this same issue: I have a problem with the UCP connection: - during "normal" operation, I get these messages every 10 minutes: 2010-08-30 15:57:09 [2280] [7] DEBUG: EMI2[vodafone-8878]: clear_sent called 2010-08-30 15:57:09 [2280] [7] INFO: EMI2[vodafone-8878]: connecting to Primary SMSC I suppose this is because the SMSC closes connection after 10 minutes of inactivity (according to Vodafone, with whom we are testing). I configured the account with keepalive = 50 but no improvement. But I am able to send and receive messages normally. - after a while (2 or 3 days) I get these messages in the log: 2010-08-30 16:07:41 [2280] [7] INFO: EMI2[vodafone-8878]: connecting to Primary SMSC 2010-08-30 16:08:02 [2280] [7] ERROR: connect failed 2010-08-30 16:08:02 [2280] [7] ERROR: System error 110: Connection timed out 2010-08-30 16:08:02 [2280] [7] ERROR: error connecting to server `217.10.194.192' at port `6001' 2010-08-30 16:08:02 [2280] [7] ERROR: EMI2[vodafone-8878]: opening TCP connection to 217.10.194.192 failed 2010-08-30 16:08:02 [2280] [7] ERROR: EMI2[vodafone-8878]: Couldn't connect to SMS center (retrying in 10 seconds). During these messages, the port is in this state (using netstat): tcp 0 1 93.113.15.3:2878 217.10.194.192:x11-1 SYN_SENT Also, with Wireshark I noticed that Kannel sends SYN packet to server port, the server returns SYN ACK, but Kannel does not return ACK. Thus, the connection isn't made successful.
So there are two questions: - is it true that an UCP client should only connect when sending a message? during inactivity, connection can be closed, and any incoming messages could be received using receive-port? - why does Kannel fails to reconnect after a while, due to failing in sending ACK message back to connecting port? Thank you!
