Past few days users are unable to send mail to gmail, by checking the logs I found the following error message "lost connection with gmail-smtp-in.l.google.com while receiving initial server greeting"
But there are no issues while sending mail to yahoo, hotmail etc.
->Tried by disabling firewall-no success
->Tried to send by directly connecting without router-no success
telnet gmail-smtp-in.l.google.com 25 Trying 18.104.22.168..<br/> Connected to gmail-smtp-in.l.google.com. Escape character is '^]'.
It just hangs there without sending the 220 greeting
I am narrowing it to ISP network issue, since I am able to telnet to same gmail server from another ISP network
what else could be causing this issue ?