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Delete Files Older Than X days in Unix or Solaris

February 5th, 2023, posted in Solaris
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Delete Files Older Than X days in Unix or Solaris,Delete Files Older Than X days in Solaris,

 

Introduction :

In Production server, there is always a need to free up the disk space from time to time. The best way to achieve is to have a cron job or an autosys job which will delete the older log files from the directory.

In this simple tutorial, we’ll quickly look at the solution to this problem. In order to delete files older than X number of days, try using Unix find command. find command is more powerful than you can really imagine. It comes up with multiple options which when gets handy can help you cover a lot of functional requirements like moving files among directories, deleting old files, archiving files etc.

Recently I came across one such requirement of deleting files older than X days from a directory in Unix server and I thought of sharing the solution with you.


Solution :

Unix find command is used to achieve the desired result.

find /path/to/the/directory/ -type f -name '*' -mtime +30 -exec rm {} \;


Explanation :

Time to breakdown the find command mentioned above :

  1. /path/to/the/directory : Edit this portion of the code with the path of your target directory.
  2. -type f : It signifies that we are targeting all the ‘files’ in the specified directory.
  3. -name ‘*’ : We have used a general regex “*” to match all the file names. You can make it more specific if you need. For example , to delete only dat files use : -name "*.dat".
  4. -mtime +30 : This refers to all the files which are older than 30 days. mtime stands for Modification time in Unix.You can change the number based on your requirement.
  5. –exec rm {} \ : This is actually the execution command which calls for deletion of all the files filtered by all the above criteria. rm stands to remove in Unix.

Although it is a very simple command, still I want you understand the usage of mtime in find command in a little more detail.

The POSIX specification for find command states that :

-mtime n The primary shall evaluate as true if the file modification time subtracted from the initialization time, divided by 86400 (with any remainder discarded), is n.

In the descriptions, wherever n is used as a primary argument, it shall be interpreted as a decimal integer optionally preceded by a plus ( ‘+’ ) or minus-sign ( ‘-‘ ) sign, as follows: +n More than n. n Exactly n. -n Less than n.

Important point to note in the above statement is that the fractional part is always ignored. So, when you specify -mtime +1 , it looks for files older more than 1 day. Rather to explain it further, it simply says to match files modified two or more days ago.

If you want to delete files older than 1 day, you can try using -mtime +0 or -mtime 1 or -mmin $((60*24)).

Would suggest you to try playing with the combinations on your own to deepen the understanding.
Still in case you have more questions, please feel free to get in touch with me.

 

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Commonly used ILOM commands

December 27th, 2022, posted in Oracle, Solaris
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Integrated Lights-out Manager (ILOM) helps to manage and troubleshoot the complete hardware of a server. With the help of ILOM we can remotely manage a server. We can power on and power off it remotely. Let us see some of the most commonly used commands in the ILOM shell.

 

Login related commands

-> start /SP/console        -- start the SP-console
-> show /SP/sessions        -- see the currently active sessions
-> stop /SP/console         -- to stop any user session

Start and stop system

-> start /SYS                            (start system)  
-> stop [-force] /SYS                    (stop system)
-> show /SYS                             (shows the power status)
-> reset /SYS                            (reset host)
-> reset /SP                             (reset ILOM SP)
-> set /HOST send_break_action=break     (send break signal to the OS)
-> reset /CMM                            (to reset CMM on a blade Chassis)

 

Locator commands

To set the locator on or off

-> set /SYS LOCATE=on
-> set /SYS LOCATE=off

Networking Commands

To see the current network configuration of ILOM

-> show /SP/network

To set an IP address for ILOM

-> set pendingipdiscovery=static 
-> set pendingipaddress=10.10.10.10
-> set pendingipnetmask=255.255.255.0
-> set pendingipgateway=10.10.10.1
-> set commitpending=true

To show SP MAC address

show /SP/network macaddress

If on a Blade chassis, to check the CMM IP :

-> show /CMM/network

User administration

-> show /SP/users                  (Display all the ILOM users)
-> show /SP/user/admin             (Display configuration settings of a specific user)
-> create /SP/users/user_name password=PWD role=[administrator|operator]    (create new user)
-> delete /SP/users/username       (Delete a user)
-> set /SP/users/admin01 role=administrator           (set the role of a user)
-> set /SP/users/admin01           (set or change password of user)

Monitoring and logs

-> show /SP/logs/event/list     (ILOM event log)
-> show -level all -output table /SP/faultmgmt     (List all hardware faults)
-> show -level all -output table /SYS type==Temperature value       (List all temperature sensor readings)

Hardware info

-> show -level all -output table /SYS type==DIMM                (show DIMMS)
-> show -level all -output table /SYS type=='Host Processor'    (show CPUs)
-> show -l all /SYS type=='Hard Disk'                           (show disks)

 

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VNC Server On Solaris

November 6th, 2022, posted in Solaris
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for S11_u10:
pkg publisher -P
pkg install solaris-desktop


Path should be :

PATH=$PATH:/usr/X11/bin
PATH=$PATH:/usr/openwin/bin
export PATH
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Find And Delete Files Older Than Some Particular Time Period In Linux

October 9th, 2022, posted in Solaris
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Searching By File Timestamp

Unix/Linux filesystems have three types of timestamp on each file. They are as follows:

  1. Access time (-atime): The timestamp when the file was last accessed.
  2. Modification time (-mtime): The timestamp when the file was last modified.
  3. Change time (-ctime): The timestamp when the metadata for a file (such as permissions or ownership) was last modified.

 

Search and delete file older than 7 days

Lets take an example, wherein we will find and delete file older than 7 days. We will be using the option “-mtime” of the find command for this.

1. Get a list of files using find command as follows:

# find /path_to_directory -mtime +7 -type f -exec ls {}\;

2. If the filenames start with any particular pattern, filter using that as follows:

# find /path_to_directory -name 'filenamepattern*' -mtime +7 -type f -exec ls {}\;

3. After checking and confirming the output, go for removal script(It is very IMPORTANT), otherwise there will be irrecoverable data loss.

# find /path_to_directory -name 'filenamepattern*' -mtime +7 -type f -exec rm -fv {}\;

# find . -name “*.pdf” -atime +7 -exec rm {} \;

4. If this needs to be done on a remote server through cron job and log the filenames of deleted files, use the following command

# ssh user@remote_ip "find /path_to_directory -name 'filenamepattern*' -mtime +7 -type f -exec rm -fv {} \; >> /tmp/backup_deletion`date +%Y%m%d`.log 2>&1"

 

Conclusion

The -mtime parameter will search for files based on the modification time; -ctime searches based on the change time. The -atime, -mtime, and -ctime use time measured in days. The find command also supports options that measure in minutes. These are as follows:

  1. -amin (access time)
  2. -mmin (modification time)
  3. -cmin (change time)

For example, to print all the files that have an access time older than seven minutes, use the following command:

# find . -type f -amin +7 -print

-newer option

The -newer option specifies a reference file with a modification time that will be used to select files modified more recently than the reference file.

Find all the files that were modified more recently than file.txt file:

# find . -type f -newer file.txt -print
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Change Solaris Zones Configurations Online

May 29th, 2022, posted in Solaris
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I assume you are aware that Solaris Zones are one of the most valuable features of Solaris since years. In this post I focus on the “Live Zone Reconfiguration” feature available since
Solaris 11.2 for Solaris Zones and since Solaris 11.3 for Kernel Zones. CPU pools, filesystems, network and disk configurations can be changed while Solaris Zones are running.

1. Limit CPU usage of a Solaris Zone using dedicated-cpu

By default Solaris Zones share the CPUs with the global and all other local Zones.
Our sample Zone currently uses 16 virtual CPUs.

# zlogin v0131 psrinfo | wc -l
16

 

We can now assign 4 dedicated virtual CPUs to be used by this Zone only.
# zonecfg -z v0131 -r "add dedicated-cpu; set ncpus=4; end"

zone 'v0131': Checking: Adding dedicated-cpu

zone 'v0131': Applying the changes

# zlogin v0131 psrinfo | wc -l
4

 

The “zonecfg -r” changes the configuration of the running Zone only.
Make sure to run the command once again to make the configuration persistent for the next Zone reboot.
# zonecfg -z v0131 "add dedicated-cpu; set ncpus=4; end"

 

2. Create and mount an additional ZFS filesystem
# zfs create v0131_data/myapp

# zonecfg -z v0131 -r "add fs; set type=zfs; set dir=/myapp; set special=v0131_data/myapp; end"

zone 'v0131': Checking: Mounting fs dir=/myapp

zone 'v0131': Applying the changes

# zlogin v0131 mount | grep myapp

/myapp on /myapp read/write/setuid/devices/rstchown/nonbmand/exec/xattr/atime/zone=v0131/nozonemod/sharezone=4/dev=d50045 on Fri Jun 10 11:56:19 2016

 

And make it persistent
# zonecfg -z v0131 "add fs; set type=zfs; set dir=/myapp; set special=v0131_data/myapp; end"
Adding network interfaces and disk devices are similar to the samples above.
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