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Changing Server Configurations

If the class hierarchy is well constructed, it is straightforward to change all dependent client configurations automatically at the same time as a server configuration is changed. Because the configuration of the whole site is held in a single place, we can also identify possible problems in advance.

For example, at our site, the default DNS servers are set by a class file which depends on the Ethernet segment. If we want to remove a DNS server from a segment, we can simply remove it from the class file and replace it with another machine. This will be detected by all clients next time they reconfigure.

It is also very simple to inspect the DNS servers being used by all the clients. This allows us to check that our old DNS server is no longer in use, before physically removing it. One advantage of the crude NIS implementation of resource maps, is that people can simply type:

  ypcat -k lcfg |grep dns.servers



Paul Anderson & Alastair Scobie