The vnc client on Windows fails to connect to the vnc server running on CentOS. I need help troubleshooting on the CentOS side please.
I have been using vnc to connect to this CentOS machine for a few years. I never had a problem until last week. Now sometimes I can connect, but most of the time I cannot.
From the Windows machine, I tested using both Ultra VNC and Real VNC. Both fail to connect.
This may be coincidental, but last week I ran yum update. yum updated several packages, and I then rebooted. I noticed that the issue started to happen shortly after this.
$ cat /etc/redhat-release
CentOS release 5.7 (Final)
$ uname -a
Linux t00539292.energy.ge.com 2.6.18-274.17.1.el5 #1 SMP Tue Jan 10 17:25:58 EST 2012 x86_64 x86_64 x86_64 GNU/Linux
The firewall is enabled. Port 5900 is open.
If I attempt to connect from another server using telnet, I see that port 5900 is open, and the vnc server responds.
bash-3.00$ telnet 22.214.171.124 5900
Connected to 126.96.36.199.
Escape character is '^]'.
I am the only CentOS system administrator, so I know that nobody else is making any changes.
How do I troubleshoot this?