Installing and Administering Internet Services

Chapter 10 321

Using rdist

Overview

To use rdist, one system in the network is designated as the master

host. The master host contains the master copy of source ﬁles that are

distributed to remote hosts.

rdist software is installed as part of the operating system. It must

reside in the /usr/bin directory on the master host and on the remote

hosts that are to be updated. It must be owned by root and must have its

access permissions set to rwsr-xr-x. The rdist process on the master

host starts an rdist process on each remote host.

rdist uses remsh as the mechanism for distributing ﬁles over the

network. In order to use rdist, you must set up remsh on each of the

remote hosts. See “Setting Up remsh” on page 323.

A ﬁle on a remote host is updated if the size or modiﬁcation time of the

ﬁle differs from the master copy. Programs that are being executed on

the remote host can be updated. The next time the program is run, the

new version of the program is executed. The owner, group, mode, and

modiﬁcation time of the ﬁles on the master host are preserved on the

remote host, if possible. The ownership of the ﬁles is preserved only if the

remote user is a superuser. Otherwise, the ﬁles are owned by the remote

user. Command line options are provided to control this behavior.

By default, the list of ﬁles updated on each remote host is printed to

standard output on the master host. You can mail the list of updated ﬁles

for a particular remote host to a speciﬁed mail recipient.

Figure 10-1 shows the distribution of source ﬁles filea1, filea2, and

filea3 from master host A to remote hosts B and C.