User Private Groups - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

Group
rpcuser
nfsnobody
pvm
apache
xfs
gdm
htt
mysql
webalizer
mailnull
smmsp
squid
ldap
netdump
pcap
quaggavt
quagga
radvd
slocate
wnn
dovecot
radiusd
Table 33.5. Standard Groups

33.5. User Private Groups

Red Hat Enterprise Linux uses a user private group (UPG) scheme, which makes UNIX groups easier
to manage.
A UPG is created whenever a new user is added to the system. A UPG has the same name as the
user for which it was created and that user is the only member of the UPG.
UPGs make it safe to set default permissions for a newly created file or directory, allowing both the
user and the group of that user to make modifications to the file or directory.
The setting which determines what permissions are applied to a newly created file or directory is called
a umask and is configured in the /etc/bashrc file. Traditionally on UNIX systems, the umask is
set to 022, which allows only the user who created the file or directory to make modifications. Under
this scheme, all other users, including members of the creator's group, are not allowed to make any
modifications. However, under the UPG scheme, this "group protection" is not necessary since every
user has their own private group.
GID
29
65534
24
48
43
42
101
27
67
47
51
23
55
34
77
102
92
75
21
49
97
95
User Private Groups
Members
487