Originally Posted by kapilbajpai88
even after restarting database, the problem is there. listner is showing that database is up and proper.
how can i check firewall settings on linux machine?? it might be due to that also, but it was working fine till monday 14th july.
do suggest what else should i try??
You don't say what kind of firewall you might have, or if you're in an environment where you might have a hardware-based firewall, or if this is even on the same network. Hard to give you any advice without knowing. You can do an "iptables -L" (as root), to see if you've got any iptables rules running. Since you're using RHEL, you can contact RedHat support, and they can help you with any firewall questions you might have.
What happened on or before Monday? Something apparently changed....what were you doing?