Red hat linux hangs during startup while starting nbclient service.
Recently we have an activity of server hardware upgrade. All went fine and the hardware of the servers are upgraded without any issues but while starting servers again after hardware upgrade, we found that two of our linux RHEL5 hosts are not coming up. We have taken console and found that it got stuck while starting nbclient service.
The system got stuck over here. I thought might be there is some issue, so i rebooted the server two more times and the result is same. The server is not going ahead of this stage.
So to start the server, we have to disable this script at boot. So to disable this script from startup we need to boot via cd. Oops that’s a bit long method. So I have taken a simple step and booted the server in init 5 or graphical mode.
Just add “5” ahead of boot parameters in grub.
And start spanssing “I” to enter into interactive mode and now spanss “y” for all services until nbclient comes. And when the system asks whether to start nbclient or not.
Just hit “n” so that this service won’t start and then spanss y for remaining services, the server will be rebooted just fine.
After the system is up and you are able to login, simply disable this service from startup.
View the service:
# chkconfig –list | grep –I nbclient
And now disable the script:
# chkconfig nbcleint off
Simply disable this script for all init/runlevel modes.
Now switch to “init 3” or runlevel 3 back so that unwanted services get killed.
If you really want to place this netbackup client script than you can have a script that starts at last during reboot and to start this in background by placing “&” in end of the command so that this will not hang the system during boot.