Network Information Services (NIS) and NFS

Source

Network Information Services (NIS) enables you to create user accounts that can be shared across all systems on your network. The user account is created only on the NIS server. NIS clients download the necessary username and password data from the NIS server to verify each user login.

An advantage of NIS is that users need to change their passwords on the NIS server only, instead of every system on the network. This makes NIS popular in computer training labs, distributed software development projects or any other situation where groups of people have to share many different computers.

The disadvantages are that NIS doesn't encrypt the username and password information sent to the clients with each login and that all users have access to the encrypted passwords stored on the NIS server. A detailed analysis of NIS security is beyond the scope of this book, but I suggest that you restrict its use to highly secure networks or to networks where access to non-NIS networks is highly restricted.

The Lightweight Directory Access Protocol (LDAP) offers similar features to NIS but has the advantage of supporting encryption without additional software and can support clients across multiple networks without the need for slave servers. It is for this reason that LDAP has become increasingly popular for this type of application. LDAP is discussed in more detail in Chapter 31, "Centralized Logins Using LDAP and RADIUS". 

Contents

• 1 Sponsors
• 2 Introduction
• 3 Scenario
• 4 Configuring The NFS Server
• 5 Configuring The NFS Client
• 6 Configuring The NIS Server
  • 6.1 Install the NIS Server Packages
  • 6.2 Edit Your /etc/sysconfig/network File
  • 6.3 Edit Your /etc/yp.conf File
  • 6.4 Start The Key NIS Server Related Daemons
    • 6.4.1 Table 30-1 Required NIS Server Daemons
  • 6.5 Initialize Your NIS Domain
  • 6.6 Start The ypbind and ypxfrd Daemons
  • 6.7 Make Sure The Daemons Are Running
• 7 Adding New NIS Users
• 8 Configuring The NIS Client
  • 8.1 Run authconfig
  • 8.2 Start The NIS Client Related Daemons
  • 8.3 Verify Name Resolution
  • 8.4 Test NIS Access To The NIS Server
  • 8.5 Test Logins via The NIS Server
    • 8.5.1 Logging In Via Telnet
    • 8.5.2 Logging In Via SSH
• 9 NIS Slave Servers
  • 9.1 Configuring NIS Slave Servers
    • 9.1.1 Table 30-2 NIS Master / Slave /etc/hosts Files
    • 9.1.2 Table 30-3 NIS Master / Slave /etc/yp.conf Files
  • 9.2 Configuring NIS Clients With Slaves
• 10 Changing Your NIS Passwords
  • 10.1 When There Is Only An NIS Master
    • 10.1.1 Users Changing Their Own Passwords
    • 10.1.2 User "Root" Changing Passwords
  • 10.2 When There Is A NIS Master / Slave Pair
  • 10.3 Possible Password Errors
    • 10.3.1 Segmentation Faults
    • 10.3.2 Daemon Errors
• 11 Considerations For A Non NFS Environment
• 12 NIS Troubleshooting
• 13 Conclusion