4285ch04.fm Draft Document for Review May 4, 2007 11:35 am
98 Linux Performance and Tuning Guidelines
On Novell SUSE and Red Hat Enterprise Linux systems, the /sbin/chkconfig command
provides the administrator with an easy-to-use interface to change start options for various
daemons. One of the first commands that should be run when using chkconfig is a check for
all running daemons:
/sbin/chkconfig --list | grep on
If you do not want the daemon to start the next time the machine boots, issue either one of
the following commands as root. They accomplish the same results, the difference being that
the second command disables a daemon on all run levels, whereas the --level flag can be
used to specify exact run levels:
/sbin/chkconfig --levels 2345 sendmail off
/sbin/chkconfig sendmail off
hpoj HP OfficeJet support. Do not disable if you plan to use an HP OfficeJet printer with your
server.
irqbalance Balances interrupts between multiple processors. You may safely disable this daemon
on a singe CPU system or if you plan to balance IRQ statically.
isdn ISDN modem support. Do not disable if you plan to use an ISDN modern with your
server.
kudzu Detects and configures new hardware. Should be run manually in case of a hardware
change.
netfs Used in support of exporting NFS shares. Do not disable if you plan to provide NFS
shares with your server.
nfslock Used for file locking with NFS. Do not disable if you plan to provide NFS shares with
your server.
pcmcia PCMCIA support on a server. Server systems rarely rely on a PCMCIA adapter so
disabling this daemon is safe in most instances.
portmap Dynamic port assignment for RPC services (such as NIS and NFS). If the system does
not provide RPC-based services there is no need for this daemon.
rawdevices Provides support for raw device bindings. If you do not intend to use raw devices you
may safely turn it off.
rpc* Various remote procedure call daemons mainly used for NFS and Samba. If the
system does not provide RPC-based services, there is no need for this daemon.
sendmail Mail Transport Agent. Do not disable this daemon if you plan to provide mail services
with the respective system.
smartd Self Monitor and Reporting Technology daemon that watches S.M.A.R.T. compatible
devices for errors. Unless you use an IDE/ SATA technology–based disk subsystem,
there is no need for S.M.A.R.T. Monitoring.
xfs Font server for X Windows. If you will run in runlevel 5, do not disable this daemon.
Attention: Turing off the xfs daemon prevents X from starting on the server. This should be
turned off only if the server will not be booting into the GUI. Simply starting the xfs daemon
before issuing the startx command enables X to start normally.
Daemons Description
