Question & Answer
Question
Expanding An Informix On-Line 5.x Database Server (UNIX) Telelogic Synergy versions 4.x only
Answer
Overview
If a Continuus/CM operation results in an Informix error message including an Informix error number followed by ISAM 131, the Informix database server most likely lacks adequate space to complete the operation. Either free space by cleaning up the databases on this Informix server, or expand the space allocated to the Informix server.
The ccmdb_server -expand command is used to expand an Informix database server. This paper provides additional information about the procedure to expand a database server’s ccm dbspace.
Solution Details
Before attempting to expand the server, you must ensure a valid backup exists for each database on the database server .This paper refers to several ccmdb_ commands, documented in the Installation and Administration Task Reference for release 4.1 and later, and in the Command Reference for 4.X releases prior to 4.1.For additional information about a server’s available space, run ccmdb_server -status -dbspace .By default, a CM Synergy Informix database server consists of three dbspaces:
the root or rootdbs dbspace,
the log dbspace, and
the ccm dbspace.
The root and log dbspaces rarely exceed their allocated space. By default, each dbspace consists of one chunk file per dbspace, but because the ccm dbspace often requires expansion, you may see that it has previously been expanded and already consists of more than one chunk file. More chunk files may be added to a dbspace as needed.Use the ccmdb_server -s -d command to confirm that the ccm dbspace is the dbspace needing expansion. For example, if ccmdb_server -s -d reports 4096 Kbytes free, there are only 4 megabytes free in the dbspace, which would be inadequate for unpacking some databases.The chunk files allocated to a dbspace are either cooked files, raw disk partitions, or portions of raw disk partitions. Additional information is available in the 4.1 Installation and Administration Task Reference , p104, 105, or the 4.0 Installation and Administration Task Reference , p76, 77.When expanding a dbspace, keep these guidelines in mind:
Before attempting to expand the server, you must ensure a valid backup exists for each database on the database server .This operation may be performed with users active in the CM Synergy databases on this server. The chunk file allocated to a dbspace cannot be reused without deleting the database server. The size specified for the chunk file must exist, either in a specified cooked file’s file system, or in the specified raw partition. The file name specified for a cooked file, or a raw partition must be an absolute path. The file name specified must be a new cooked file, or a new raw disk partition (or a new offset on an existing raw disk partition), not an existing pathname already used in the dbspace. You’re expanding a dbspace by adding a new chunk file: you’re not expanding a chunk file. The cooked file or raw disk partition must be physically local to this system. Do not use an NFS-mounted device for a chunk file.
Hints: When specifying a size with the ccmdb_server -expand command’s -size option, the size you specify is in kbytes, where 10000 kbytes equals 10 megabytes. For example, to expand a dbspace by 10 MB, specify -;s ize 10000 .
If you are using cooked files, the -offset option is not used. The -offset option is only used if a raw disk partition is used in the following manner: Assume a server was created on a single 200 MB raw disk partition such that the server’s 20000 KB root dbspace was located on that partition at offset 0, the 8000 KB log dbspace was located on that same partition at offset 20000, and the 40000 KB first ccm dbspace was located on that same partition at offset 28000. You decide to expand the ccm dbspace by another 40 MB. ccmdb_server -s -d reports that the dbspaces are presently allocated to use 68 MB of the partition. Your system administrator confirms that the entire 200 MB partition is available for the Informix server, and you’ve confirmed that the existing 68 MB started at offset 0 of the partition. More than 40 MB is therefore available for your use. Specify -size 40000 -offset 68000 to the ccmdb_server -e command.
If using cooked files, the chunk file directory needs to be owned by informix, with group informix, and permissions rwxrwx--- (770). Cooked files or raw disk partitions used for chunk files need to be owned by informix, with group informix, and permissions rw-rw---- (660). If you’ve confirmed that your existing cooked chunk file directory’s file system has sufficient space, and you simply want to add another cooked file to the ccm dbspace, you can rely on certain defaults. For example, given:
% ccmdb_server -s -d
*** database server land ***
server number: 9
state: On-Line
maximum users allowed: 10
number of users: 0
archive device: /dev/null
network service: land_land
--- dbspace rootdbs ---
total free space: 11242 Kbytes
chunk files:
/usr/chunks/land_root.dbs 12560 Kbytes total, 11242 Kbytes free
--- dbspace log ---
total free space: 1828 Kbytes
chunk files:
/usr/chunks/land_log.dbs 10240 Kbytes total, 1828 Kbytes free
--- dbspace ccm ---
total free space: 20056 Kbytes
chunk files:
/usr/chunks/land_ccm.dbs 20480 Kbytes total, 20056 Kbytes free
%
The next command defaults to servername=hostname, -dbspace ccm , -offset 0 , and the pathname is expanded to include a newly-named file, land_ccm_2.dbs.
% ccmdb_server -expand -size 20000 -p /usr/chunks -y
WARNING: dbspace not specified, use the default dbspace (ccm)
WARNING: chunk offset not set, use the default offset (0 Kbytes)
Preparing chunk file '/usr/chunks/land_ccm_2.dbs' for dbspace creation...
*************************************************************
database server name: land
--- expand dbspace ---
dbspace name: ccm
chunk size: 20000 Kbytes
chunk offset: 0 Kbytes
chunk path: /usr/chunks/land_ccm_2.dbs
current chunk files:
/usr/chunks/land_ccm.dbs
*************************************************************
Preparing chunk files for dbspace expansion ...
Dbspace 'ccm' has been expanded by '20000' Kbytes
%
The resultant server configuration looks like this:
% ccmdb_server -s -d
*** database server land ***
server number: 9
state: On-Line
maximum users allowed: 10
number of users: 0
archive device: /dev/null
network service: land_land
--- dbspace rootdbs ---
total free space: 11242 Kbytes
chunk files:
/usr/chunks/land_root.dbs 12560 Kbytes total, 11242 Kbytes free
--- dbspace log ---
total free space: 1828 Kbytes
chunk files:
/usr/chunks/land_log.dbs 10240 Kbytes total, 1828 Kbytes free
--- dbspace ccm ---
total free space: 40050 Kbytes
chunk files:
/usr/chunks/land_ccm.dbs 20480 Kbytes total, 20056 Kbytes free
/usr/chunks/land_ccm_2.dbs 20000 Kbytes total, 19994 Kbytes free
%
Related Information
Historical Number
KB1517;TB121
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Document Information
Modified date:
22 December 2020
UID
swg21325163