VOS_RELEASE(1)						       AFS Command Reference						    VOS_RELEASE(1)

NAME

       vos_release - Updates read-only volumes to match the read/write source volume

SYNOPSIS

       vos release -id <volume name or ID> [-force]
	   [-cell <cell name>]
	   [-noauth] [-localauth]
	   [-verbose] [-encrypt] [-noresolve] [-help]

       vos rel -i <volume name or ID>
	   [-f] [-c <cell name>]
	   [-noa] [-l] [-v] [-e] [-nor] [-h]

DESCRIPTION

       The vos release command copies the contents of the indicated read/write source volume to each read-only site defined in the source volume's
       Volume Location Database (VLDB) entry. (Use the vos addsite command to define sites as necessary before issuing this command). Each read-
       only copy has the same name as read/write source with the addition of a ".readonly" extension.

       For users to have a consistent view of the file system, the release of the new volume version must be atomic: either all read-only sites
       receive the new version, or all sites keep the version they currently have. The vos release command is designed to ensure that all copies
       of the volume's read-only version match both the read/write source and each other. In cases where problems such as machine or server
       process outages prevent successful completion of the release operation, AFS uses two mechanisms to alert the administrator.

       First, the command interpreter generates an error message on the standard error stream naming each read-only site that did not receive the
       new volume version. Second, during the release operation the Volume Location (VL) Server marks site definitions in the VLDB entry with
       flags ("New release" and "Old release") that indicate whether or not the site has the new volume version. If any flags remain after the
       operation completes, it was not successful. The Cache Manager refuses to access a read-only site marked with the "Old release" flag, which
       potentially imposes a greater load on the sites marked with the "New release" flag. It is important to investigate and eliminate the cause
       of the failure and then to issue the vos release command as many times as necessary to complete the release without errors.

       The pattern of site flags remaining in the volume's VLDB entry after a failed release operation can help determine the point at which the
       operation failed. Use the vos examine or vos listvldb command to display the VLDB entry. The VL Server sets the flags in concert with the
       Volume Server's operations, as follows:

       o   Before the operation begins, the VL Server sets the "New release" flag on the read/write site definition in the VLDB entry and the "Old
	   release" flag on read-only site definitions (unless the read-only site has been defined since the last release operation and has no
	   actual volume, in which case its site flag remains "Not released").

       o   If necessary, the Volume Server creates a temporary copy (a clone) of the read/write source called the ReleaseClone (see the following
	   discussion of when the Volume Server does or does not create a new ReleaseClone.) It assigns the ReleaseClone its own volume ID number,
	   which the VL Server records in the "RClone" field of the source volume's VLDB entry.

       o   The Volume Server distributes a copy of the ReleaseClone to each read-only site defined in the VLDB entry. As the site successfully
	   receives the new clone, the VL Server sets the site's flag in the VLDB entry to "New release".

       o   When all the read-only copies are successfully released, the VL Server clears all the "New release" site flags. The ReleaseClone is no
	   longer needed, so the Volume Server deletes it and the VL Server erases its ID from the VLDB entry.

       By default, the Volume Server determines automatically whether or not it needs to create a new ReleaseClone:

       o   If there are no flags ("New release", "Old release", or "Not released") on site definitions in the VLDB entry, the previous vos release
	   command completed successfully and all read-only sites currently have the same volume. The Volume Server infers that the current vos
	   release command was issued because the read/write volume has changed. The Volume Server creates a new ReleaseClone and distributes it
	   to all of the read-only sites.

       o   If any site definition in the VLDB entry is marked with a flag, either the previous release operation did not complete successfully or
	   a new read-only site was defined since the last release. The Volume Server does not create a new ReleaseClone, instead distributing the
	   existing ReleaseClone to sites marked with the "Old release" or "Not released" flag. As previously noted, the VL Server marks each VLDB
	   site definition with the "New release" flag as the site receives the ReleaseClone, and clears all flags after all sites successfully
	   receive it.

       To override the default behavior, forcing the Volume Server to create and release a new ReleaseClone to the read-only sites, include the
       -force flag. This is appropriate if, for example, the data at the read/write site has changed since the existing ReleaseClone was created
       during the previous release operation.

OPTIONS

       -id <volume name or id>
	   Specifies either the complete name or volume ID number of a read/write volume.

       -force
	   Creates a new ReleaseClone and distributes it all read-only sites regardless of whether or not any site definitions in the VLDB entry
	   are marked with a flag.

       -cell <cell name>
	   Names the cell in which to run the command. Do not combine this argument with the -localauth flag. For more details, see vos(1).

       -noauth
	   Assigns the unprivileged identity "anonymous" to the issuer. Do not combine this flag with the -localauth flag. For more details, see
	   vos(1).

       -localauth
	   Constructs a server ticket using a key from the local /etc/openafs/server/KeyFile file. The vos command interpreter presents it to the
	   Volume Server and Volume Location Server during mutual authentication. Do not combine this flag with the -cell argument or -noauth
	   flag. For more details, see vos(1).

       -verbose
	   Produces on the standard output stream a detailed trace of the command's execution. If this argument is omitted, only warnings and
	   error messages appear.

       -encrypt
	   Encrypts the command so that the operation's results are not transmitted across the network in clear text. This option is available in
	   OpenAFS versions 1.4.11 or later and 1.5.60 or later.

       -noresolve
	   Shows all servers as IP addresses instead of the DNS name. This is very useful when the server address is registered as 127.0.0.1 or
	   when dealing with multi-homed servers. This option is available in OpenAFS versions 1.4.8 or later and 1.5.35 or later.

       -help
	   Prints the online help for this command. All other valid options are ignored.

EXAMPLES

       The following command clones the read/write volume usr and releases it to the read-only sites defined in its VLDB entry.

	  % vos release usr

PRIVILEGE REQUIRED

       The issuer must be listed in the /etc/openafs/server/UserList file on the machine specified with the -server argument and on each database
       server machine. If the -localauth flag is included, the issuer must instead be logged on to a server machine as the local superuser "root".

SEE ALSO

       vos(1), vos_addsite(1), vos_examine(1), vos_listvldb(1)

COPYRIGHT

       IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

       This documentation is covered by the IBM Public License Version 1.0.  It was converted from HTML to POD by software written by Chas
       Williams and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.

OpenAFS 							    2012-03-26							    VOS_RELEASE(1)