onspaces -m: Start mirroring

Use the onspaces -m option to start mirroring for a dbspace, blobspace, or sbspace.

Figure 1: Syntax:

1  onspaces -m
1 dbspace
1 blobspace
1 sbspace
1+ ,
1    -p pathname   -o offset   -m pathname offset
1   -f filename
3?   -y

This command has an equivalent SQL administration API function.

Element Purpose Key considerations
-f filename Indicates that chunk-location information is in a file named filename The file must be a buffered file that already exists. The path name must conform to the operating-system-specific rules for path names.

For more information, see Using a File to Specify Chunk-Location Information with the -f Option.
-m Adds mirroring for an existing dbspace, blobspace, or sbspace User-data chunks in a mirrored sbspace need not be mirrored.

The mirrored chunks should be on a different disk. You must mirror all the chunks at the same time.
-m pathname offset The second time that pathname occurs in the syntax diagram, it indicates the disk partition or unbuffered device of the initial chunk of the dbspace, blobspace, or sbspace that performs the mirroring.

The second time offset appears in the syntax diagram, it indicates the offset to reach the mirrored chunk of the newly mirrored dbspace, blobspace, or sbspace. Also see the entries for pathname and offset in this table.

 None.
-o offset The first time that offset occurs in the syntax diagram, it indicates, in kilobytes, the offset into the disk partition or into the unbuffered device to reach the initial chunk of the newly mirrored dbspace, blobspace, or sbspace. Restrictions: Unsigned integer. The starting offset must be equal to or greater than 0. The starting offset plus the chunk size cannot exceed the maximum chunk size.

The maximum offset is 4 terabytes.

For more information, see allocating raw disk space on UNIX™, in the chapter on managing disk space in the HCL OneDB™ Administrator's Guide.
-p pathname The first time pathname occurs in the syntax diagram, it indicates the disk partition or unbuffered device of the initial chunk of the dbspace, blobspace, or sbspace that you want to mirror. The chunk must be an existing unbuffered device or buffered file. When you specify a path name, you can use either a full path name or a relative path name. However, if you use a relative path name, it must be relative to the directory that was the current directory when you initialized the database server.

For path name syntax, see your operating-system documentation.
-y Causes the database server to automatically respond yes to all prompts None.
blobspace Names the blobspace that you want to mirror Syntax must conform to the Identifier segment; see HCL OneDB Guide to SQL: Syntax. For more information, see the chapter on using mirroring in the HCL OneDB Administrator's Guide.
dbspace Names the dbspace that you want to mirror Syntax must conform to the Identifier segment; see HCL OneDB Guide to SQL: Syntax. For background information, see the chapter on using mirroring in the HCL OneDB Administrator's Guide.
sbspace Names the sbspace that you want to mirror Syntax must conform to the Identifier segment; see HCL OneDB Guide to SQL: Syntax. For background information, see the chapter on using mirroring in the HCL OneDB Administrator's Guide.