ATA isn't registered in VPS asterisk server


I’m having trouble with an ATA GS HT503 in my network. ATA doesn’t register in VPS asterisk server. Everything was working well when done in the very first time the network was deployed. After, ATA was damaged, then changed in warranty by new one.

If I test ATA with a virtual asterisk server in my LAN, it works. Dialplan works fine. If I test ATA with a VPS asterisk server, doesn´t work. ATA doesn’t register. I had reviewed new ATA’s configuration and had had changes respect damaged. I had tested VPS asterisk server ports, especifically 5060 from outside and then appears to be closed. However in VPS asterisk server the port seems to be ok, but not listening.

I want to review network conditions of VPS asterisk server to determine if there is a missconfiguration that avoid ATA would be registered.

Anyone can help me? sugestions are welcome…

Thanks in advance.

Check if Asterisk server is listening netstat apn | grep -i asterisk

Also in check your iptables rules

iptables -L -n
also you can turn off iptables temporarily , service iptables stop or /etc/init.d/iptables stop

also enable the sip debug and check if there is any register request