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How to manage rc script using chkconfig?

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39.How to manage rc script using chkconfig?
Ans.
1. Fedora core and Red hat enterprise Linux come with a useful tool called ‘chkconfig’.

 2. It helps the system administrator to manage rc script and xinetd configuration files without having to manipulate them directly.

 3. Type ‘chkconfig –list’ to see all the services chkconfig knows about, and whether they are started or stopped on each runlevel.

 4. Example:
atd 0:off 1:off 2:off 3:on 4:on 5:on 6:off
The first column is a name of the installed service, the next 7 columns represents a runlevel and tell us whether that service is turned on or off in that runlevel.

 5. To turn a service on or off using chkconfig, we use following syntax:
Chkconfig –level[0-6] (you must choose a runlevel) servicename off|on|reset

 6. To turn off the gpm daemon turned on previously, type:
chkconfig –level 2 gpm off

 7. To turn on xinetd type:
chkconfig xined on

 8. Run chkconfig –list again to check the changed services are set to the state we desire.

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