UGID_ALLOC.RANGE(5)

NAME
ugid_alloc.range - range of user IDs and group IDs to allocate

SYNOPSIS
/etc/ugid_alloc.range

AVAILABILITY

Available only on Sun 386i systems running a SunOS 4.0.x release or earlier. Not a SunOS 4.1 release feature.

DESCRIPTION

The /etc/ugid_alloc.range file, if it exists on the Network Information Service (NIS) master of the passwd.byuid map (or the group.bygid map for group IDs), specifies the user IDs and group IDs that can be allocated for the local NIS domain by the uid_allocd(8C) daemons. If the file does not exist, user IDs or group IDs may be allocated beginning at 100 and ending at 60,000; no user IDs or group IDs are allocated out of that range in any case. If the local NIS domain is not listed in this file, no user IDs or group IDs will be allocated. Otherwise, this file specifies ranges of user IDs or group IDs that may be allocated. The different NIS domains on a network can use identical copies of this file.

If a network has multiple NIS domains, each one will typically use ranges for its user IDs and group IDs that do not overlap with the other NIS domains, guaranteeing that user IDs and group IDs are unique throughout the network. Without guarantees of user ID and group ID uniqueness, network tools and services which rely on that uniqueness for security or authentication will not work as intended. Such services include NFS, except for the “Secure NFS,” which has other solutions for security and authentication. Note: the required uniqueness could be guaranteed by mechanisms other than automatic allocation within manually configured ranges. For example, some sites can use a function of their employee numbers during manual user ID allocation, and coordinate group ID assignment verbally.

This file can contain blank lines. Comments begin with a `#' character and extend to the end of the current line. The first token on the line is an NIS domain name. It is separated from the second token by white space (SPACE or TAB characters). The second token is either user or group, indicating that the line specifies user ID or group ID ranges, respectively. The third token is a comma-separated list of user or group ID ranges in that domain. These ranges take two forms: a single number specifies just that ID, and two numbers separated by a dash specify all IDs starting at the first number and ending with the second.

For example, the following file would direct that the manufacturing department at a particular company use user IDs from 700 to 999 or 1200 to 1499. Accounts created by tools in the NIS domain for manufacturing would use a user ID in those ranges, and those user accounts could safely be added to one of the other NIS domains if desired (by manually transferring NIS map data between the domains). Group IDs are allocated only within the administration domain.

    # Three departments share our site's network, and each has its
    # own Ethernet and master server connected with IP routers.
    # This file sets the user ID ranges assigned to each department.
    # Groups are defined by the administration group only.
    YP.admin.company.com | user | 500-699
    YP.manufacturing.company.com | user | 700-999
    YP.engineering.company.com | user | 100-499,1000-1199
    YP.manufacturing.company.com | user | 1200-1499
    YP.admin.company.com | group | 100-60000

SEE ALSO
passwd(5), group(5), uid_allocd(8C)

BUGS

There is a limit of forty ranges for each domain; more ranges are silently ignored.

NOTES

The Network Information Service (NIS) was formerly known as Sun Yellow Pages (YP). The functionality of the two remains the same; only the name has changed.