Name

group − group file

Description

The group file is an ASCII file that contains the following information for each group:

Group name
Encrypted password
Numerical group ID
Comma-separated list of all users allowed in the group

Each group name is separated from the next by a new line.  The fields are separated by colons.  If the password field is null, no password is demanded. 

Because of the encrypted passwords, it can and does have general read permission and can be used, for example, to map numerical group IDs to names. 

The group database can be distributed in a network by a naming service, such as Yellow Pages or BIND/Hesiod.  See the Guide to the Yellow Pages Service or the Guide to the BIND/Hesiod Service for setup information. 

Restrictions

The passwd() command will not change the passwords.

Increasing the number of groups that a user is in beyond 8 can affect services that use SUN RPC.  The version of SUN RPC shipped with ULTRX V4.2 supports up to 32 groups.  Prior versions supported users being in up to 8 groups.  Users who increase the number of groups that they are a member of to more than 8 will not be able to NFS mount file systems from ULTRIX servers older than V4.2.  If root group membership is increased to more than 8 groups on a V4.2 system, the YP service may not work if that V4.2 system is in a mixed YP server environment where there are both V4.2 and previous releases of YP servers.  Again, this incompatibility can only occur if a user’s or root’s group membership is increased to more than 8 groups. 

Files

/etc/group

See Also

passwd(1), setgroups(2), crypt(3), getgrent(3), initgroups(3x), passwd(5)
Guide to the BIND/Hesiod Service
Guide to the Yellow Pages Service