Metric Collection Error oracle.sysman.emSDK.emd.comm.CommException: java.io.IOException: Cannot establish proxy connection: 503 Service Unavailable java.net.NoRouteToHostException: No route to host
In Oracle Enterprise Manager Grid Control, the Agents, Hosts, Listeners were all displaying correctly with status of ‘up’.
But the databases reported status of “Metric Collection Error”.
When I tried to configure a database, the configure database page displayed either one of these errors at top of page:
oracle.sysman.emSDK.emd.comm.CommException: java.io.IOException: Cannot establish proxy connection: 503 Service Unavailable oracle.sysman.emSDK.emd.comm.CommException: java.net.NoRouteToHostException: No route to host
Problem was agent server firewall settings blocking ports.
Fix for me was:
1) on agent server as oracle
cd /software/oracle/product/agent10g/bin ./emctl status agent
Look for “Agent URL” in the output of that command, in my case that was
2) On Grid Control server as oracle, paste that line into a wget command at the command prompt:
wget --no-check-certificate https://myagentserver.mydomain:3872/emd/main
That failed with: “failed: No route to host”, fix was as below:
3) On agent server again – as root
Make backup copy before changing settings:
cd /etc/sysconfig cp -p iptables iptables.backup
Add a new line for port 3872 by copying one of the existing lines, e.g.:
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 3872 -j ACCEPT
service iptables restart
This worked for me with Oracle Enterprise Manager Grid Control and Agent both version 10.2.0.5 and both on 32 bit linux.