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|_____|___|_| \_|\___//_/\_\

USER QUOTA HOWTO

Verifiably applicable to Redhat 7.2 - 9.0 and reasonably 
applicable to any Linux distribution.
___________________________________________________________
                                     Created Sept 2003 v2.0

section A: Ten Steps to User Quotas ............. (line 20)
section B: Syntax and Command Usage ............. (line 69)
section C: Real ISP Implementation Example ..... (line 104)

___________________________________________________________
          |             section A: Ten Steps to User Quotas
steps:

1). Do you need to patch your kernel?
    * if you are using a recent version of RH with the RH
    supplied kernel, then no.

2). Do you need to install quota?
    * if you are using a recent version of RH with quota
    installed, then no.  The most recent version of quota
    as of this writing is quota 3.06 - 9.

3.) Modify /etc/fstab and add support for quota on the file
    system(s) you intend to regulate.  Hopefully, when you
    installed linux you allocated partitions appropriately
    to benefit the most from user quota implementation.

    example: Adding quota to a mail server, the path
    /var/spool/mail is a seperate partition.  In fstab it
    looked like this prior to modification:

    LABEL=/var/spool/mail  /var/spool/mail  ext3  defaults  1 2

    To enable user quota support on a file system, add 
    "usrquota" to the 4th field containing the word "defaults"

    LABEL=/var/spool/mail  /var/spool/mail  ext3  defaults,userquota  1 2

    Replace "usrquota" with "grpquota", should you need 
    group quota support on a file system.

4.) Since you modified fstab, reboot the computer.

5.) create the necessary files on the partition where you 
    enabled quota.  Create the files 'aquota.group' and
    'aquota.user'. Activate the quota database.

    example: 'touch /var/spool/mail/aquota.user'
    'touch touch /var/spool/mail/aquota.group'
    'chmod /var/spool/mail/aquota.* 600'
    'quotacheck /var/spool/mail'

6.) Create a cron job to update the quota database. Quota 
    automatically should work with periodical checks, it 
    sometimes helps to run quotacheck periodically.

    example: 0 3 * * 0 /sbin/quotacheck -avug

___________________________________________________________
          |             section B: Syntax and Command Usage
usage:

    Assigning quota to a specif user or group is 
    accomplished with the command 'edquota'.  To display
    all quota limits use the command 'repquota'.

    example: 'edquota -u username'
    'repquota -a'

    To rapidly set quotas for many users all at once use
    the following syntax (all users with uid 500 and up).
    Sets everyone to the same quota as 'username')

    example: edquota -p username `awk -F: '$3 > 499 {print $1}' /etc/passwd`

    The commands 'quotaon' turns on quota accounting and 
    'quotaoff' to turns it off. 

definitions:

    Soft Limit: usage on filesystem that triggers grace 
    period.

    Hard Limit: maximum usage limit before write access is 
    denied to the user.

    Grace Period: period triggered by soft limit before
    access is denied to the user.

    Block Limits: total accumulated file disk usage.

    File Limits: total number of files or inodes.

___________________________________________________________
          |      section C: Real ISP Implementation Example 
intro:

    In this example an ISP uses quota to limit the size of 
    customer mailboxes on /var/spool/mail for /dev/sda2.
    
    Disk quotas were enabled using the procedure described
    above.  Now our goals are as follows:

goals:

    1. establish default quotas for a mail system already
    containing 100 or more users.

    example: start by setting the first user's quota to the 
    values to be the system default.

             edquota -u derek

    second use a simple shell script to duplicate those 
    values to every mailbox owner all at once.

             edquota -p derek `awk -F: '$3 > 499 {print $1}' /etc/passwd

    2. synchronize the quota database for the filesystem
    on /dev/sda2.

    example: quotaoff /var/spool/mail
             /sbin/quotacheck -avug
             quotaon /var/spool/mail

    3. generate a report showing only users exceeding their
    mailbox disk quota.

    example: repquota -ta | grep -v "\-\-\ \ \ "

    4. configure warnquota to send mail to users over quota
    by creating or modifying the warnquota.conf file.

    example: vi /etc/warnquota.conf

    use the following values in warnquota.conf

    MAIL_CMD        = "/usr/sbin/sendmail -t"
    FROM            = "support@ispname.com"
    SUBJECT         = NOTE: Your mailbox has exceeded allocatted disk space limits
    CC_TO           = "support@ispname.com"
    SUPPORT         = "support@ispname.com"
    PHONE           = "555 555-1212"
    MESSAGE         = Your mailbox has exceeded the allotted limit\
     on this server|Please delete any unnecessary email in your mailbox on:|
    SIGNATURE       = This message is automatically generated by the mail system.

    5. send customers over soft limit an email notification
    
    example: warnquota 

    6. create a daily cron process script that will syn-
    chronize the quota database, send an email notification
    to mailbox owners exceeding soft quota, and send an 
    email report to the system administrator which includes
    users exceeding their mailbox disk quota.

    example: create a cron script, make it executable and
    add the appropriate shell commands.

             touch /etc/cron.daily/quotatasks
             chmod +x /etc/cron.daily/quotatasks
             vi /etc/cron.daily/quotatasks

shell script example:

#!/bin/bash
#
# Derek B. Winterstien
#######################################
#
/sbin/quotaoff /var/spool/mail
/sbin/quotacheck -avug
/sbin/quotaon /var/spool/mail
sleep 5s
/usr/sbin/warnquota
echo "From: System <null@culverin.ispdomain.com>" > /tmp/mmail.lastmessage.txt
echo "To: recipients@ispdomain.com" >> /tmp/mmail.lastmessage.txt
echo "Subject: cron daily - quotatasks execution" >> /tmp/mmail.lastmessage.txt
echo "Attention:" >> /tmp/mmail.lastmessage.txt
echo "quotatasks executed." >> /tmp/mmail.lastmessage.txt
/bin/date >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
echo "System mailbox quota report:" >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
echo "Showing only users over disk quota" >> /tmp/mmail.lastmessage.txt
/usr/sbin/repquota -ta | grep -v "\-\-\ \ \ " >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
echo "Customers exceeding soft quota have been notified by email." >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
echo "System, " >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
echo "Derek B. Winterstien" >> /tmp/mmail.lastmessage.txt 
echo " " >> /tmp/mmail.lastmessage.txt
echo "_______________________________________________________________" >> /tmp/mmail.lastmessage.txt
echo "www.ispdomain.com - High Speed Internet Connections To The World" >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
echo " " >> /tmp/mmail.lastmessage.txt
#
/usr/sbin/sendmail noc@ispdomain.net,support@ispdomain.net < /tmp/mmail.lastmessage.txt