Author: Stephen R Lang

This is just a quick reference page for using find to do basic things.

Find is a pretty powerful tool that accepts a bunch of options for narrowing down your search. Some basic examples of stuff you can do are below.

Find a specific file type and extension older than 300 days and remove them

This will find files:
– Older than 300 days
– Is a file
– Match *.jpg
– Will not go into sub directories

This also works for those pesky directories that have millions of files.

First, always confirm the command will work before blindly removing files:

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find . -maxdepth 1 -type f -name '*.jpg' -mtime +300 | xargs ls -al

Once you verified that the files displayed are the ones you want removed, remove them by running:

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find . -maxdepth 1 -type f -name '*.jpg' -mtime +300 | xargs rm -f

Find files with 777 permissions

This will find all files that have 777 permissions:

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find . -type f -perm 0777 -print

This will find all files that do NOT have 777 permissions

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find / -type f ! -perm 777

Find Files with 777 Permissions and change to 644

Use caution with this, this is generally not smart to run blindly as it will go into subdirectories unless you set maxdepth.

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find . -type f -perm 0777 -print -exec chmod 644 {} \;

Find Directories with 777 Permissions and change to 755

Use caution with this, this is generally not smart to run blindly as it will go into subdirectories unless you set maxdepth.

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find . -type d -perm 777 -print -exec chmod 755 {} \;

Find empty directories

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find /tmp -type d -empty

Find all hidden files within a directory

[root@web01 ~]# find /path/to/directory -type f -name ".*"

Find files owned by user or group

[root@web01 ~]# cd /path/to/directory
[root@web01 ~]# find /var/www -user apache
[root@web01 ~]# find /var/www -group apache

Find files that were modified in the last 30 days

[root@web01 ~]# find / -mtime 30

Find files that were modified in the last hour

[root@web01 ~]# find / -mmin -60

Find files that were changed within the last hour
Note, this one is specified in minutes only!

[root@web01 ~]# find / -cmin -60

Find files that were accessed in the last 5 days

[root@web01 ~]# find / -atime 5

Find files that were accessed within the last hour
Note, this one is specified in minutes only!

[root@web01 ~]# find / -amin -60

Count files per directory with find
This one is useful when you need to find the top 10 directories that contain the most amount of files.

[root@web01 ~]# vim count-files-per-directory.sh
#!/bin/bash

if [ $# -ne 1 ];then
  echo "Usage: `basename $0` DIRECTORY"
  exit 1
fi

echo "Please wait..."

find "$@" -type d -print0 2>/dev/null | while IFS= read -r -d '' file; do 
    echo -e `ls -A "$file" 2>/dev/null | wc -l` "files in:\t $file"
done | sort -nr | head | awk '{print NR".", "\t", $0}'

exit 0

Now run it against the / directory:

[root@web01 ~]# bash count-files-per-directory.sh /
Please wait...
1. 	 768 files in:	 /usr/share/man/man1
2. 	 631 files in:	 /usr/lib64/python2.6
3. 	 575 files in:	 /usr/share/locale
4. 	 566 files in:	 /usr/share/vim/vim74/syntax
5. 	 496 files in:	 /usr/bin
6. 	 487 files in:	 /usr/share/man/man8
7. 	 393 files in:	 /usr/share/perl5/unicore/lib/gc_sc
8. 	 380 files in:	 /usr/include/linux
9. 	 354 files in:	 /usr/lib64/python2.6/encodings
10. 	 334 files in:	 /usr/share/man/man3

Or if you only need to run the search in a specific directory:

[root@web01 ~]# bash count-files-per-directory.sh /usr/share/man
Please wait...
1. 	 768 files in:	 /usr/share/man/man1
2. 	 487 files in:	 /usr/share/man/man8
3. 	 334 files in:	 /usr/share/man/man3
4. 	 124 files in:	 /usr/share/man/man5
5. 	 49 files in:	 /usr/share/man
6. 	 35 files in:	 /usr/share/man/ru/man8
7. 	 31 files in:	 /usr/share/man/man7
8. 	 27 files in:	 /usr/share/man/fr/man8
9. 	 25 files in:	 /usr/share/man/de/man8
10. 	 22 files in:	 /usr/share/man/ja/man8

HP comes with their server utility scripts called hpssacli and hpacucli. These tools allow you to view and modify your hardware configuration on the server. The hpacucli is the older implementation of the toolkit, but the syntax is pretty similar.

HP tools information

To show the firmware version, run:

[root@web01 ~]# hpasmcli -s "show server"

If you want to see extended information, run:

[root@web01 ~]# hpssacli controller all show config detail

General information

To view information regarding the server model, cpu, type, memory, etc, run:

[root@web01 ~]# hpasmcli -s "show server"

Hardware Health

If you want to view the health of the system and chassis components, run:

[root@web01 ~]# hpasmcli -s "show server"

The chassis can also only return specific components, such as:

[root@web01 ~]# hpasmcli -s "show powersupply"
[root@web01 ~]# hpasmcli -s "show dimm"
[root@web01 ~]# hpasmcli -s "show fans"
[root@web01 ~]# hpasmcli -s "show temp"

Storage health

To view the physical and virtual disks on the server:

[root@web01 ~]# hpssacli ctrl all show config
[root@web01 ~]# hpssacli controller slot=3 physicaldrive all show
[root@web01 ~]# hpssacli controller slot=3 physicaldrive 2I:1:5 show detail
[root@web01 ~]# hpssacli controller slot=3 logicaldrive all show

On older HP servers, you can view the physical and virtual disks on the server by:

[root@web01 ~]# hpacucli controller slot=1 physicaldrive all show
[root@web01 ~]# hpacucli controller slot=1 physicaldrive 2I:1:5 show detail
[root@web01 ~]# hpacucli controller slot=1 logicaldrive all show

To see the storage battery status:

[root@web01 ~]# hpssacli controller all show detail | egrep -i 'battery\/|controller\ status|cache\ status'
   Controller Status: OK
   Cache Status: OK
   Battery/Capacitor Count: 1
   Battery/Capacitor Status: OK

Hardware logs

To display the hardware logs:

[root@web01 ~]# hpasmcli -s "show iml"

If you need to clear the hardware logs:

[root@web01 ~]# hpasmcli -s "clear iml"

CPU actions

To see if hyperthreading is enabled on the CPUs:

[root@web01 ~]# hpasmcli -s "show ht"

If you wanted to change the hyperthreading settings:

# Enable
[root@web01 ~]# hpasmcli -s "enable ht"

# Disable
[root@web01 ~]# hpasmcli -s "disable ht"

Dell comes with their server utility scripts called omreport and omconfig. These tools allow you to view and modify your hardware configuration on the server.

Dell tools information

To see what version of the tools your running:

[root@web01 ~]# omreport about details=true

To see if there are updates available for the firmware:

[root@web01 ~]# omreport system version

To see what commands are available using omreport:

[root@web01 ~]# omreport system -?

General information

To view information regarding the server model, cpu type, memory, service tags, etc, run:

[root@web01 ~]# omreport system summary

Hardware Health

If you want to view the health of the system and chassis components, run:

[root@web01 ~]# omreport system

To only get the health information for the chassis:

[root@web01 ~]# omreport chassis

The chassis can also only return specific components, such as:

[root@web01 ~]# omreport chassis fans
[root@web01 ~]# omreport chassis memory
[root@web01 ~]# omreport chassis nics
[root@web01 ~]# omreport chassis processors
[root@web01 ~]# omreport chassis temps
[root@web01 ~]# omreport chassis batteries
[root@web01 ~]# omreport chassis pwrsupplies

Storage health

As a quick note, if the commands below report there are no controllers listed, check to be sure that the software is actually running by:

[root@web01 ~]# /opt/dell/srvadmin/sbin/srvadmin-services.sh status
dell_rbu (module) is stopped
ipmi driver is running
dsm_sa_datamgrd is stopped
dsm_sa_eventmgrd is stopped
dsm_sa_snmpd is stopped
dsm_om_shrsvcd is stopped
dsm_om_connsvcd is stopped
[root@web01 ~]# /opt/dell/srvadmin/sbin/srvadmin-services.sh restart

To view the physical and virtual disks on the server:

[root@web01 ~]# omreport storage pdisk controller=0
[root@web01 ~]# omreport storage vdisk controller=0
[root@web01 ~]# omreport storage pdisk controller=0 vdisk=0

If you just wanted a quick listing of the relevant disk information to see the state of the drives, run:

[root@web01 ~]# omreport storage pdisk controller=0 | grep -iE "^id|^status|name|state|Failure Predicted"
ID                              : 0:0:0
Status                          : Ok
Name                            : Physical Disk 0:0:0
State                           : Online
Failure Predicted               : No
ID                              : 0:0:1
Status                          : Ok
Name                            : Physical Disk 0:0:1
State                           : Online
Failure Predicted               : No

To see if there are any empty drive bays on the server:

[root@web01 ~]# omreport storage controller controller=0 info=pdslotreport | grep 'Empty Slots'

To see the storage battery status:

[root@web01 ~]# omreport storage battery controller=0

Hardware Logs

To display the hardware logs, run:

[root@web01 ~]# omreport system esmlog

If you need to view the alert logs:

[root@web01 ~]# omreport system alertlog

And if you needed to view the messages from the POST:

[root@web01 ~]# omreport system postlog

If you find you need to clear the logs, that can be performed by:

[root@web01 ~]# omconfig system esmlog action=clear
[root@web01 ~]# omconfig system alertlog action=clear
[root@web01 ~]# omconfig system postlog action=clear

CPU actions

To see if hyperthreading is enabled on the CPUs:

[root@web01 ~]# omreport chassis biossetup | grep -A 2 'HyperThreading'

If you wanted to enable hyperthreading:

# Dell R710
[root@web01 ~]# omconfig chassis biossetup attribute=cpuht setting=enabled

# Dell R720
[root@web01 ~]# omconfig chassis biossetup attribute=ProcCores setting=All

If you needed to enable or disable NUMA:

# Disable NUMA:
[root@web01 ~]# omconfig chassis biossetup attribute=numa setting=disabled

# Enable NUMA:
[root@web01 ~]# omconfig chassis biossetup attribute=numa setting=enabled

The systems timezone is usually set during installation. If the timezone needed to be changed, it can be done without rebooting the system.

Just be sure to watch for applications like MySQL and PHP that require additional steps for changing the timezone, which are noted near the bottom of this article.

CentOS 5 and CentOS 6

Modify the zone in /etc/sysconfig/clock. You can find the valid timezones in /usr/share/zoneinfo. The commonly used timezones include America/New_York, America/Chicago, America/Los_Angeles, and UTC.

[root@web01 ~]# vim /etc/sysconfig/clock
...
ZONE="America/New_York"
...

Then update /etc/localtime:

[root@web01 ~]# tzdata-update

Now sync the hardware clock against the system time:

[root@web01 ~]# hwclock --systohc

Go ahead and restart syslogd/rsyslogd and crond:

[root@web01 ~]# service crond restart
[root@web01 ~]# service rsyslog restart
[root@web01 ~]# service syslog restart

CentOS 7

Changing the timezone on CentOS 7 can be done with a few commands. You can find the valid timezones in /usr/share/zoneinfo. The commonly used timezones include America/New_York, America/Chicago, America/Los_Angeles, and UTC.

[root@web01 ~]# timedatectl set-timezone America/New_York
[root@web01 ~]# systemctl restart crond
[root@web01 ~]# systemctl restart rsyslog

Ubuntu 12.04 and Ubuntu 14.04

Modify the zone in /etc/timezone. You can find the valid timezones in /usr/share/zoneinfo. The commonly used timezones include America/New_York, America/Chicago, America/Los_Angeles, and UTC.

[root@web01 ~]# vim /etc/timezone
...
America/New_York
...

Now update active timezone:

[root@web01 ~]# dpkg-reconfigure --frontend noninteractive tzdata
Current default time zone: 'America/New_York'
Local time is now:      Tue Jan 17 01:18:04 EST 2017.
Universal Time is now:  Tue Jan 17 06:18:04 UTC 2017.

Restart rsyslog and cron:

[root@web01 ~]# service cron restart
[root@web01 ~]# service rsyslog restart

Ubuntu 16.04

Changing the timezone on Ubuntu 16.04 can be done with a few commands. You can find the valid timezones in /usr/share/zoneinfo. The commonly used timezones include America/New_York, America/Chicago, America/Los_Angeles, and UTC.

[root@web01 ~]# timedatectl set-timezone America/New_York
[root@web01 ~]# systemctl restart crond
[root@web01 ~]# systemctl restart rsyslog

MySQL, Percona and MariaDB

In order for MySQL, Percona, and MariaDB to register the new timezone settings, they need to be restarted. There really isn’t a way around this. As a temporary solution, and one that will not pick up future DST timezone changes, you can manually set the databases current time by:

# List current system date and time via MySQL:
[root@web01 ~]# mysql
mysql> SELECT @@global.time_zone;

# List the current date and time according to MySQL:
mysql> SELECT NOW();

# Update the timezone using the UTC offset:
mysql> SET @@global.time_zone = '+05:00';

Even with this temporary fix in place, unless you are using the UTC timezone, MySQL should be restarted very soon.

PHP

PHP should also have its timezone updated when you change it on the system. Determine where your php.ini resides, then update it accordingly. I am assuming CentOS 6 for this example:

[root@web01 ~]# vim /etc/php.ini
...
date.timezone = "America/New_York"
...

Then restart Apache or PHP-FPM for your system so the changes are applied. Afterwards, test the timezone change to PHP by:

[root@web01 ~]# php -i |grep date.timezone
date/time support => enabled
date.timezone => America/New_York => America/New_York

A list of supported timezone configurations for PHP can be found at:
http://www.php.net/manual/en/timezones.php

The hostname of a system is usually set during installation. However as time goes on, it may be determined that the hostname should be changed to something more suitable.

Outlined below is the procedure for changing the systems hostname without having to reboot.

CentOS 5 and 6

First, check to see what the existing hostname is on the server:

[root@web01 ~]# hostname

Then change the current hostname. In this example, we’re going to change the hostname to web04.mydomain.com:

[root@web01 ~]# hostname web04.mydomain.com

Now update /etc/hosts with the new hostname:

[root@web01 ~]# vim /etc/hosts
127.0.0.1      localhost.localdomain.com localhost
192.168.1.5    web04.mydomain.com web04

If you have ‘domain’ specified in /etc/resolv.conf, update that accordingly. There is not a need to add ‘domain’ if it is not already defined:

[root@web01 ~]# vim /etc/resolv.conf
domain web04.mydomain.com
nameserver 8.8.8.8
nameserver 8.8.4.4

Next update your network configuration:

[root@web01 ~]# vim /etc/sysconfig/network
...
HOSTNAME=web04.mydomain.com
...

Restart syslog so the new changes go into effect:

# CentOS 5
[root@web01 ~]# service syslog restart

# CentOS 6
[root@web01 ~]# service rsyslog restart

Finally, log out and back into the server via SSH and you should see the new hostname in effect. Also check /var/log/secure and /var/log/messages to ensure the new hostname is being used.

CentOS 7

In this example, we’re going to change the hostname to web04.mydomain.com. First run:

[root@web01 ~]# hostname web04.mydomain.com

Now update /etc/hosts with the new hostname:

[root@web01 ~]# vim /etc/hosts
127.0.0.1      localhost.localdomain.com localhost
192.168.1.5    web04.mydomain.com web04

Now update the hostname using the systemd command:

[root@web01 ~]# hostnamectl set-hostname web04.mydomain.com

If you have ‘domain’ specified in /etc/resolv.conf, update that accordingly. There is not a need to add ‘domain’ if it is not already defined:

[root@web01 ~]# vim /etc/resolv.conf
domain web04.mydomain.com
nameserver 8.8.8.8
nameserver 8.8.4.4

Now restart syslog so the new changes go into effect:

[root@web01 ~]# systemctl restart rsyslog

Finally, log out and back into the server via SSH and you should see the new hostname in effect. Also check /var/log/auth.log and /var/log/syslog to ensure the new hostname is being used.

Ubuntu 12.04 and Ubuntu 14.04

First, check to see what the existing hostname is on the server:

[root@web01 ~]# hostname

In this example, we’re going to change the hostname to web04.mydomain.com. So run:

[root@web01 ~]# hostname web04.mydomain.com

Now update /etc/hosts with the new hostname:

[root@web01 ~]# vim /etc/hosts
127.0.0.1      localhost.localdomain.com localhost
192.168.1.5    web04.mydomain.com web04

If you have ‘domain’ specified in /etc/resolv.conf, update that accordingly. There is not a need to add ‘domain’ if it is not already defined:

[root@web01 ~]# vim /etc/resolv.conf
domain web04.mydomain.com
nameserver 8.8.8.8
nameserver 8.8.4.4

Then update /etc/hostname accordingly:

[root@web01 ~]# vim /etc/hostname
web04.mydomain.com

Now restart syslog so the new changes go into effect:

[root@web01 ~]# service rsyslog restart

Finally, log out and back into the server via SSH and you should see the new hostname in effect. Also check /var/log/auth.log and /var/log/syslog to ensure the new hostname is being used.

Ubuntu 16.04 and Ubuntu 18.04

First, check to see what the existing hostname is on the server:

[root@web01 ~]# hostname

In this example, we’re going to change the hostname to web04.mydomain.com. So run:

[root@web01 ~]# hostname web04.mydomain.com

Now update /etc/hosts with the new hostname:

[root@web01 ~]# vim /etc/hosts
127.0.0.1      localhost.localdomain.com localhost
192.168.1.5    web04.mydomain.com web04

Now update the hostname using the systemd command:

[root@web01 ~]# hostnamectl set-hostname web04.mydomain.com

If you have ‘domain’ specified in /etc/resolv.conf, update that accordingly. There is not a need to add ‘domain’ if it is not already defined:

[root@web01 ~]# vim /etc/resolv.conf
domain web04.mydomain.com
nameserver 8.8.8.8
nameserver 8.8.4.4

Now restart syslog so the new changes go into effect:

[root@web01 ~]# systemctl restart rsyslog

On Ubuntu 18.04 only, check to see if /etc/cloud/cloud.cfg exists. If it does, confirm the preserve hostname is set to true as shown below:

[root@web01 ~]# vim /etc/cloud/cloud.cfg
...
preserve_hostname: true
...

Finally, log out and back into the server via SSH and you should see the new hostname in effect. Also check /var/log/auth.log and /var/log/syslog to ensure the new hostname is being used.