Skip Navigation Links | |
Exit Print View | |
Sun QFS and Sun Storage Archive Manager 5.3 Reference Manual Sun QFS and Sun Storage Archive Manager 5.3 Information Library |
1. User Commands (Man Pages Section 1)
2. Maintenance Commands (Man Pages Section 1M)
3. Library Functions (Man Pages Section 3)
4. Library Functions (Man Pages Section 3X)
5. File Formats (Man Pages Section 4)
NAME sammkfs, samfsinfo - Constructs or displays information for a Sun QFS or SAM-QFS file system SYNOPSIS /opt/SUNWsamfs/sbin/sammkfs [-a allocation_unit] [-i inodes] [-A] [-P] [-S] [-V] fs_name /opt/SUNWsamfs/sbin/samfsinfo fs_name AVAILABILITY SUNWqfs SUNWsamfs DESCRIPTION The sammkfs command creates a Sun QFS or SAM-QFS file system from the disk partitions that belong to the family set fs_name, where fs_name is the family set name as defined in the mcf file. Up to 252 disk partitions can be specified in the mcf file for a Sun QFS or SAM-QFS file system. The sammkfs command can also be used to recreate a file system after a disaster. The sammkfs command can create either a version 2 file system that is backwards compatible with previous releases, or a version 2A file system that has new features, but is not compatible with previous releases. By default, a version 2A file system is created. See -P parameter below for details on the new features, and how to create a version 2 file system. The sammkfs command aligns the block allocation bit maps and round robins them on the metadata devices for improved performance. This behavior is backwards compatible with previous releases. The option feature Aligned Maps is set. The samfsinfo command displays the structure of an existing Sun QFS or SAM-QFS file system. The output is similar to that obtained by using the -V option to the sammkfs command. OPTIONS These commands accept the following options: -a allocation_unit Specifies the disk allocation unit (DAU). The DAU is the basic unit of online storage. When you specify a DAU size, you specify the number of 1024-byte (1 kilobyte) blocks to be allocated for a file. The DAU size you can specify depends on the type of file system being initialized, as follows: o The SAM-QFS file system is an ms file system. The disk devices in it are all md devices. Both data and metadata are written to the md devices. The allocation_unit specifies the DAU to be used for the md devices. Possible allocation_unit specifications are 16, 32, or 64 (the default). o The Sun QFS or SAM-QFS file systems are ma file systems. The metadata in these file systems is written to mm devices. The disk devices in these file systems are specified as either md, mr, or gXXX devices, as follows: - For the md devices, possible allocation_unit specifications are 16, 32, or 64 (the default). A single file system cannot have md devices mixed among the mr and gXXX devices. - For mr devices, the DAU is fully adjustable. Specify an allocation_unit that is a multiple of 8 in the following range for mr devices: 8 < allocation_unit < 65528. The default is 64. - For gXXX devices, which specify striped groups, the DAU is fully adjustable. If the file system contains striped groups, the minimum unit of disk space allocated is the DAU multiplied by the number of members in the striped group. Specify an allocation_unit that is a multiple of 8 in the following range for gXXX devices: 8 < allocation_unit < 65528. The default is 256. You can mix mr and gXXX devices in a single Sun QFS or SAM-QFS file system. If these device types are mixed, the allocation_unit specified is used for both device types. If no allocation_unit is specified, the DAU size used for each type of device is 256. -i inodes Specifies the number of inodes to be allocated for this file system. This is the total number of user inodes that can be used for the life of this file system. In Sun QFS and SAM-QFS version 2 superblock file systems, a number of inodes are reserved for file system usage, and are unavailable to the user. This number is in addition to the specified number of user inodes. The actual number of inodes available vary from that specified, due to rounding to metadata DAU size. NOTE: By specifying this option, you eliminate the possibility of ever increasing the number of inodes for the file system. Therefore, Sun does not recommend the use of this option. When this option is specified, later use of the samgrowfs(1M) command increases the size of the file system, but it cannot increase the number of allowable inodes. For more information on enlarging file systems, see the WARNINGS section of this man page and the samgrowfs(1M) man page. -A Uses NFSv4 ACL style for the filesystem ACLs instead of POSIX ACL style. This feature is available only in releases of Solaris beyond Solaris 10. -P Specifies that a previous version of the file system be created. This version creates a version 2 superblock and is compatible with SAM-QFS version 4.6. This version cannot use the following features however: large host table, extended attributes, and online grow. Without the -P parameter, a version 2A superblock is created, the above features are available, and the file system is not usable with SAM-QFS version 4.6 or previous. -S Indicates that this file system is shared. In order to mount the file system as a Sun QFS shared file system, you must also create a hosts.fs_name configuration file. For more information on this configuration file and other aspects of the Sun QFS shared file system, see the Sun QFS File System Configuration and Administration Guide. For information on configuring a hosts file, see the hosts.fs(4) man page. -V Writes configuration information to standard output but does not execute the sammkfs command. This information can be used to create a new file system. The samfsinfo command should be used to generate configuration information for an existing file system. EXAMPLES Example 1. The following command creates SAM-QFS file system with a DAU size of 128 kilobytes: server# sammkfs -a 128 samfs1 FILES /etc/opt/SUNWsamfs/mcf The configuration file for a Sun QFS or SAM-QFS file system WARNINGS As with creating any type of file system, if you specify the wrong partition names, you risk damaging user or system data. Be sure to specify partitions that are otherwise unused on your system. Do not use overlapping partitions. With SAM-QFS 4.1 and greater AND Solaris 64bit kernels which support large disk devices (greater than 1 TB), it is possible to have partitions that are greater than 1 TB. Note that these file systems are not usable on Solaris systems that do not support large disk devices. SEE ALSO dd(1M), samd(1M), samgrowfs(1M), undamage(1M). mcf(4). Sun QFS File System Configuration and Administration Guide. Sun Storage Archive Manager Configuration and Administration Guide. WARNINGS Be careful when using the -i inodes option for this command. By using this option, you dictate the maximum number of inodes allowed for the life of this file system. This eliminates the possibility of ever using the samgrowfs(1M) command to increase the number of files in this file system. After a file system is made with -i specified, the samgrowfs(1M) command can only be used to increase the size of the file system in terms of bytes. NOTES Data alignment refers to matching the allocation unit of the RAID controller with the allocation_unit of the file system. A mismatched alignment causes a read-modify-write operation for I/O that is less than the block size. The optimal alignment formula is as follows: allocation_unit = RAID_stripe_width * number_of_data_disks For example, if a RAID-5 unit has a total of 8 disks with 1 of the 8 being the parity disk, the number of data disks is 7. If the RAID stripe width is 64 kilobytes, then the optimal allocation_unit is 64 * 7 = 448.