NAME

uid_allocd, gid_allocd − userid and groupid allocator daemons

SYNOPSIS

/usr/etc/rpc.uid_allocd
/usr/etc/rpc.gid_allocd

AVAILABILITY

Sun386i systems only. 

DESCRIPTION

The UID (or GID) allocator temporarily allocate an unused UID (or GID) for use by account administration tools.  It maintains a cache of UIDs (or GIDs) that have been allocated by potentially multiple tools (or instances of tools) in a distributed system, so that they can create accounts (or groups) concurrently.  It also provides the ability to safely enter a UID (or GID) into the cache which was allocated using some other method, such as manually by an administrator; and the ability to delete entries from the cache.  Entries in this cache persist for at least an hour even through system crashes. 

These allocators are available on the system which contains the master copy of the list of UIDs (or GIDs).  Since this list is currently maintainted using Yellow Pages, the service is available on the master of the passwd.byuid (group.bygid) YP map.  The service could be provided using a UID database service other than Yellow Pages. 

This implementation uses DES authentication (the Sun Secure RPC protocol) to restrict access to this function.  The only clients privileged to allocate UIDs (or GIDs) are those whose net IDs are in the accounts group (fixed at GID 11). All machine IDs are allowed to allocate UIDs (or GIDs). 

If the file /etc/ugid_alloc.range exists, the allocator only allocates UIDs (or GIDs) in the range listed there.  This feature is intended to be used by sites which have multiple YP domains on their networks; each YP domain would be assigned a unique range of UIDs (or GIDs).  If the file exists, and the local YP domain is not explicitly assigned a unique range of UIDs or GIDs, none will be allocated. 

FILES

/var/yp/domainname/passwd.byuid.{dir,pag}

/var/yp/domainname/group.bygid.{dir,pag}

/var/yp/domainname/netid.byname.{dir,pag}

/etc/uid_alloc.cache

/etc/gid_alloc.cache

/etc/ugid_alloc.range

/usr/include/rpcsvc/uid_alloc.x

/usr/include/rpcsvc/gid_alloc.x

SEE ALSO

snap(1), ugid_alloc.range(5), logintool(8)

BUGS

Using UID (or GID) ranges does not solve the problem that two different machines, or groups of machines, may assign different meaning to a given UID (or GID). 

The current implementation of the daemon is tuned towards small lists of active UIDs (or GIDs), both in YP and in the cache it maintains. 

Sun Release 4.0  —  Last change: 17 July 1989