j2edlimit Command

Purpose

Manages quota Limits Classes for JFS2 file systems.

Syntax

To edit Quota Limits Classes:

j2edlimit [ -e ] [ -u | -g ] Filesystem

To list Quota Limits Classes:

j2edlimit -l [ -u | -g ] Filesystem

To Set an Existing Limits Class as the Default Limits Class:

j2edlimit -d LimitsClassID [ -u | -g ] Filesystem

To Assign a User or Group to a Limits Class:

j2edlimit -a LimitsClassID [ -u UserName | -g GroupName ] Filesystem

Description

Quotas are managed in JFS2 file systems through the use of Limits Classes. Each Limits Class has hard and soft limits for disk space and file, and grace periods for exceeding the soft limits. Individual users and groups may be assigned to a Limits Class and are then subject to the quotas defined by that class. Any user or group not assigned to a class is subject to the quotas defined by the default class (Class ID 0). Quota limits for all users or groups in a particular class can be changed by using j2edlimit to modify the Limits Class, without having to change or duplicate quotas for each user or group. By default, or when used with the -e flag, the j2edlimit command edits the User Limits Classes for the file system specified on the command line. When used with the -g flag, the j2edlimit command edits the Group Limits Classes for the specified file system. The command creates a temporary file that contains the file system's current limits classes, then invokes the vi editor (or the editor specified by the EDITOR environment variable) on the temporary file so that the limits classes can be added and modified. When the editor is exited, the command reads the temporary file and modifies the binary quota files to reflect any changes.

Note: If you specify an editor in the EDITOR environment variable, you must use the full pathname of the editor.

Fields displayed in the temporary file are:

Block Hard Limit: The total amount of 1KB blocks the user or group will be allowed to use, including temporary storage during a quota grace period.
Block Soft Limit: The number of 1KB blocks the user or group will be allowed to use during normal operations.
File Hard Limit: The total number of files the user or group will be allowed to create, including temporary files created during a quota grace period.
File Soft Limit: The number of files the user or group will be allowed to create during normal operations.
Block Grace Period: Amount of time a user can exceed the Block Soft Limit before it becomes enforced as a hard limit.
File Grace Period: Amount of time a user can exceed the File Soft Limit before it becomes enforced as a hard limit.

Note:

A hard limit with a value of 1 indicates that no allocations are permitted. A soft limit with a value of 1, in conjunction with a hard limit with a value of 0, indicates that allocations are permitted only on a temporary basis. Hard or soft limits can be specified in kilobytes (the default), megabytes, or gigabytes.
A user can exceed established soft limits for the length of the corresponding grace period. Upon expiration of the grace period, the soft limit is enforced as a hard limit. The grace period can be specified in days, hours, mnutes, or seconds. A value of 0 indicates that the default grace period is imposed; a value of 1 second indicates that no grace period is granted.
After changing a grace period using the j2edlimit command, users who have already reached their old grace period must reduce their file system usage to a level below their soft limits in order to use the new grace period. In the future, when these users exceed their soft limits, the new grace period will be in effect.

Flags

Item	Description
-a	Assigns the User or Group specified by the -u or -g flag to the indicated Limits Class in the file system specified on the command line.
-d	Sets the indicated Limits Class as the default for the file system specified on the command line. By default, or with the -u flag, the default is set for User quotas. With the -g flag, the default is set for Group quotas.
-e	Edits the Limits Classes for the file system specified on the command line (this is the default operation for the j2edlimit command). By default, or with the -u flag, the default is set for User quotas. With the -g flag, the default is set for Group quotas.
-g	When used with the -d, -l or optional -e flag, performs the peration on the Group Limits Classes for the file system specified on the command line. When used with the -a flag, assigns the associated Group to the specified Limits Class. Note: If the parameter contains all numbers then it will be treated as a Group ID, and the Group ID will be assigned to the Limits Class.
-l	Lists the Limits Classes for the file system specified on the command line. By default, or with the -u flag, User limits classes are listed. With the -g flag, Group limits classes are listed. The format of the listing is the same as found in the temporary file when editing Limits Classes.
-u	When used with the -d, -l or optional -e flag, performs the operation on the User Limits Classes for the file system specified on the command line. When used with the -a flag, assigns the associated User to the specified Limits Class. Note: If the parameter contains all numbers then it will be treated as a User ID, and the User ID will be assigned to the Limits Class.

Security

Access Control: Only the root user can execute this command.

Attention RBAC users and Trusted AIX users: This command can perform privileged operations. Only privileged users can run privileged operations. For more information about authorizations and privileges, see Privileged Command Database in AIX® Version 7.1 Security. For a list of privileges and the authorizations associated with this command, see the lssecattr command or the getcmdattr subcommand.

Examples

To edit User Limits Classes for the /home file system:
```
j2edlimit /home
```
To list Group Limits Classes for the /home file system:
```
j2edlimit -l -g /home
```
To set User Limits Class ID 2 as the default for the /foo file system:
```
 j2edlimit -d2 /foo
```
To assign user markg to Limits Class ID 1 in the /home file system:
```
 j2edlimit -a 1 -u markg /home
```

Files

Item	Description
quota.user	Contains usage and Limits information for users.
quota.group	Contains usage and Limits information for groups.
/etc/filesystems	Contains file system names and locations.