ABSTRACT
Probably most NTP users are not concerned about designing and deploying large NTP subnets because their needs may simply be to find a convenient server or three somewhere and plug a few lines into the NTP configuration file. If that is the case, read only the first section of this chapter and put the rest off until you need it. However, system and network administrators should understand the basic principles of NTP subnet engineering because it can be easy to do something evil, such as generate the same configuration files for 1000 machines all pointing to a dinky time server on the other side of the planet. This has happened more than once. Another popular evil is when some stalwart server changes IP address for some reason and hundreds of clients continue hammering on the old address for years afterward. This too has happened more than once.
