tag:blogger.com,1999:blog-16261334716983499382026-04-08T14:35:28.894+05:30Sharing Knowledge | System Admin ArticlesLazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.comBlogger336125tag:blogger.com,1999:blog-1626133471698349938.post-2583007411736004862024-04-11T23:47:00.002+05:302024-04-11T23:47:28.434+05:30

Search in all branches in the repogit grep "search_term" $(git branch -a --format "%(refname)")

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-79013082569686320812024-04-11T23:42:00.001+05:302024-04-11T23:42:26.775+05:30

Update JSON file using jq commandcat app.json | jq --arg environment "VVPAT" --arg test "0102023" '.myapp.configuration.labels += {environment: $environment, test:$test}'  > modified_app.json

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-69310330286653992092022-09-09T22:25:00.003+05:302022-09-09T22:26:12.739+05:30

In GitHub Action workflows, there is no direct way to repeat the same job or step using variables. We have to use the "matrix" to achieve this.Example:my_loop_job: name: loop job runs-on: my-github-runners strategy: matrix: my_variable: [ "var1", "var2", "var3" ]         steps: - name: test loop run: |       &

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-79482040057477144722018-12-26T22:31:00.003+05:302019-11-05T23:09:34.487+05:30

To reset the jenkins admin password, You can simply disable the security in the config.xml file. 1. If your jenkins is running on the Linux OS, edit the below file. vi /var/lib/jenkins/config.xml file. 2. Search for the word <useSecurity>true</useSecurity> and change the word true to false.  3. Restart the Jenkins server. service jenkins restart 4.

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com7tag:blogger.com,1999:blog-1626133471698349938.post-89553129350189054992018-05-21T16:52:00.000+05:302018-05-21T17:25:05.538+05:30

Issue:  dracut fails when you trying to create initramfs image file. [root@linux_server1 boot]# dracut -f /boot/initramfs-2.6.39-400.298.2.el6uek.x86_64.img 2.6.39-400.298.2 E: Failed to install /etc/system-fips [root@linux_server1 boot]# ls -l /boot/initramfs-2.6.39-400.298.2.el6uek.x86_64.img ls: cannot access /boot/initramfs-2.6.39-400.298.2.el6uek.x86_64.img: No such file or

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-45861304184515065252018-01-17T23:25:00.000+05:302018-01-17T23:25:54.457+05:30

 You often used "for loop" in shell script to gather an information from large number of your Linux / Unix infrastructure servers. However if your server count is more, it may take lot of time to finish the task. Do you think it will be good if the ssh sessions to remote servers run in parallel? Since the modern day servers having multi-core CPU's we can utilize the real parallel and

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com1tag:blogger.com,1999:blog-1626133471698349938.post-40293261526494440492017-11-16T16:56:00.001+05:302017-11-16T16:58:38.900+05:30

In Linux, You may wonder what are the files inside a rpm package and you may want to check them before installing it. You can do this with the below rpm commands: If the rpm file available locally: [root@linux_server1 ~]# rpm -qlp telnet-0.17-48.el6.x86_64.rpm /usr/bin/telnet /usr/share/man/man1/telnet.1.gz [root@linux_server1 ~]# [root@linux_server1 ~]# rpm -q -filesbypkg -p

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com2tag:blogger.com,1999:blog-1626133471698349938.post-52179017564467153202017-02-16T20:51:00.001+05:302017-02-16T20:51:42.894+05:30

   You will notice that your PCS web interface is not working after your pacemaker cluster installation. Because it is not enabled by default. Here is the steps to enable it. cd /usr/lib/pcsd vi pcsd.rbsearch for "DISABLE_GUI=true" edit that line to "DISABLE_GUI=false"service pcsd restart Now you will be able to access the pacemaker web interface as below: https://&lt

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-69191273421246500482014-11-19T18:34:00.000+05:302014-11-19T18:34:07.949+05:30

nscd (Name Service Cache Daemon) daemon provides caching service for the name service requests in Linux. To configure the nscd caching service, edit /etc/nscd.conf To Flush the DNS Cache in Linux server: # /etc/init.d/nscd restart              OR   # service nscd restart Hope this helps..

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com1tag:blogger.com,1999:blog-1626133471698349938.post-82863058817797849462014-02-17T16:56:00.000+05:302014-11-05T22:14:03.879+05:30

I/O schedulers in Linux noop - It can be helpful for devices that do I/O scheduling themselves, as intelligent storage, or devices that do not depend on mechanical movement cfq - A fairness-oriented scheduler. It tries to maintain system-wide fairness of I/O bandwidth deadline - A latency-oriented I/O scheduler. Each I/O request has got a deadline assigned.

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com2tag:blogger.com,1999:blog-1626133471698349938.post-1055785770676039312013-08-17T09:02:00.001+05:302013-08-26T12:40:55.794+05:30

Recently I had a request to reduce the swap space and allocate that space to some other LV in one of our server.  Below is what I followed and it perfectly worked for me.  :) Make sure you have enough physical memory to hold the swap contents.  Now, turn the swap off: # sync # swapoff <YOUR_SWAP_PARTITION> Now check the status # swapon -s  Then, Use fdisk

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-52877727575847616542013-01-05T18:25:00.001+05:302013-01-05T18:25:24.006+05:30

1. CHECK UNASSIGNED DRIVES THAT CAN BE USED  server1:~ # hpacucliHP Array Configuration Utility CLI 8.70-8.0Detecting Controllers...Done.Type "help" for a list of supported commands.Type "exit" to close the console.   => hpacucli ctrl all show config  Smart Array P400 in Slot 9 (sn: P61XXXXXXXXXN) array A (SAS, Unused Space: 0 MB) logicaldrive 1 (68.3

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-89367181727262774062013-01-05T17:46:00.000+05:302013-01-05T17:53:59.943+05:30

When you are working in an UNIX shell using Putty tool, you may get this error. Problem:  When you are trying to open vi editor, you may get error message "Terminal too wide" How to Fix this?? Enter the below command in the shell and try to open vi editor again. It will work. stty columns 120 Hope this will help on someone.

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com2tag:blogger.com,1999:blog-1626133471698349938.post-4011015555846888032012-09-09T18:26:00.001+05:302012-09-10T11:56:00.508+05:30

Many thanks to RAM for this Article. --- This article explains, Filesystem extension on live Linux VMware Linux Guest where vmdisk size is extended and by not new disk added. We had a scenario as follows: 1.       File system extension requirement on a live mounted file system without reboot. 2.       It’s a

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com1tag:blogger.com,1999:blog-1626133471698349938.post-9654526771303908822012-08-14T19:57:00.000+05:302012-08-14T19:57:21.029+05:30

To Allow web and ssh connections in IP Tables SSH and web both require out going messages on established tcp connections. iptables -A OUTPUT -o eth0 -m state –state ESTABLISHED,RELATED -j ACCEPT Then you need to allow incomming connections on port 80 and 22 and possibly 443 iptables -A INPUT -p tcp -i eth0 –dport 22 –sport 1024:65535 -m state –state NEW -j ACCEPTiptables -A INPUT -p tcp -i

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-14783687321710107232012-08-14T18:20:00.001+05:302014-11-05T22:39:09.371+05:30

what is the difference between migratepv and replacepv? replacepv command simply moves all the logical partitions on one physical volume to another physical volume.  The command is designed to make it easy to replace a disk in a mirrored configuration. migratepv command also very similar. The biggest difference is that migratepv allows you to copy the LPs on a logical volume basis, not

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-28420033247357215082012-08-14T17:40:00.000+05:302012-08-14T17:40:08.944+05:30

umask will be used for setting the default file creation permissions.When a file is created, its permissions are set by default, depending on the umask setting configured. This value is usually set for all users in /etc/profile and can be obtained by typing command umask: testuser$ umask0022 The default umask value is usually 022. It is an octal number which indicates what rights will

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com1tag:blogger.com,1999:blog-1626133471698349938.post-61855979055409347002012-08-14T17:21:00.000+05:302012-08-14T17:21:22.344+05:30

Adding default Gateway in Linux SUSE To change the default route permanently in SuSe Linux, make an entry in /etc/sysconfig/network/routes file. For example, to make 192.168.10.1 as default route, add the following line into /etc/sysconfig/network/routes file.  default 192.168.2.1 - - Using route command: To route all the traffic via 192.168.1.1 gateway connected via eth1 network

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com1tag:blogger.com,1999:blog-1626133471698349938.post-17692978615078895972012-08-14T17:09:00.000+05:302012-08-14T17:09:03.895+05:30

We can set useful limits for users which is useful to control the resource utilization in Linux. This can be configured in /etc/security/limits.conf. To activate these limits you need to add the following line to the bottom of /etc/pam.d/login file in your Linux server. session required /lib/security/pam_limits.so. Entries in limits.conf file have the following structure: [

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com4tag:blogger.com,1999:blog-1626133471698349938.post-82686443881800516792012-08-14T16:20:00.000+05:302012-08-14T16:21:06.605+05:30

Below are the special shell variables. These are important to know for everyone, especially who is willing to learn shell scripting. Hope the list helps. Name Description $1 - $9 These variables are referring the parameters passed to command or script. $1 refers to the first argument and $2 refers second and so on. $0 The name of the

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-52011875645042705712012-06-03T15:51:00.001+05:302012-07-02T10:09:37.400+05:30

We have faced a strange issue recently and would like to share that to LazySystemAdmin readers. Problem / Issue: After upgrading the kernel, we rebooted the server. After reboot, some of the Ethernet network cards (NIC) are renamed to '__tmpxxxx' instead of ethX. Ethernet  interface keeps changing into  '__tmpxxxx' even after two more reboot of the server. "ifconfig -a" output

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com3tag:blogger.com,1999:blog-1626133471698349938.post-69994211262611730292012-05-10T20:34:00.001+05:302012-05-10T20:34:48.000+05:30

What is the major difference between ext2 and ext3 file systems? The main difference between ext2 and ext3 is, ext3 allows journaling. (Journaling is a type of log file, which tracks all the file system changes. so that you can recover in case of filesystem crash) Explain Linux Booting Process? When the computer is switched on, it automatically invokes BIOS [a ROM chip embedded in the

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com4tag:blogger.com,1999:blog-1626133471698349938.post-62357037354800559002012-04-02T20:20:00.000+05:302012-04-02T21:13:58.838+05:30

I  have came across the situation where multiple kblockd process are utilizing the CPU heavily and causing server load high in Linux servers. I was wondered what is kblockd and why it is taking high CPU utilization. But there is not much information available in internet about kblockd. After lot of  research, the below is what I learned. What is kblockd? In a general, the

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com5tag:blogger.com,1999:blog-1626133471698349938.post-87262351122333175312012-02-28T23:53:00.001+05:302012-02-29T00:14:35.012+05:30

How do you disable ping to Linux server? Here is the quick steps:  To disable ping: echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all To enable ping: echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all That's all..! 

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0tag:blogger.com,1999:blog-1626133471698349938.post-46280281802753892932012-02-28T23:49:00.000+05:302012-02-28T23:49:17.876+05:30

In AIX 5.3, To change the default length of username: # chdev -l sys0 -a max_logname=9sys0 changed To check the current length of username: # lsattr -El sys0 -a max_lognamemax_logname 9 Maximum login name length at boot time True# getconf LOGIN_NAME_MAX 21 Hope this quick tip helps someone..!

LazySystemAdminhttp://www.blogger.com/profile/01907118252758913311noreply@blogger.com0