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If you want to know what is Network Teaming, please check out this link. In this post, I’m going to just list all the commands required to setup a team interface. Let’s list the available network interfaces I have on my server. $ nmcli dev status DEVICE TYPE STATE CONNECTION enp1s0 ethernet connected enp1s0 enp7s0 ethernet connected student virbr0 bridge connected (externally) virbr0 enp8s0 ethernet disconnected -- enp9s0 ethernet disconnected -- lo loopback unmanaged -- virbr0-nic tun unmanaged -- From the above output, you probably can guess that I’m going to use enp8s0 and enp9s0 to create a team network interface....

If you’re a seasoned Linux user, you may have used source command once or twice before. You might also have used ., the exactly same command, instead. Both source and . are shell builtin commands. I have used this many times, but I only used for one purpose which is to read the environment variables from a file to the current shell environment. So, when I was asked during a job interview, “What does source do?...

I normally use dwm as the Windows manager on my laptop. However, I occationally need to switch to Plasma to test some applications out. This laptop is currently running Fedora 34 which has been upgraded from previous versions as old as 28, I believe. When I run Dolphin, there is an annoying error message “Could ont enter folder tags:/”. Though it doesn’t cause any problems, it’s very annoying. I found a solution from bug report #437176 suggesting to purge Baloo database....

I just setup a new server with a minimal installation of AlmaLinux 8. AlmaLinux is a variant of free Red Hat Enterprise Linux 8. It’s like a CentOS 8, but will have a full support until the end of RHEL 8 life cycle. This server is to serve as a new proxy for all VMs inside my home lab. I want to use tinyproxy which is need to be compiled from source as the RPM package is not available as of the time writing....

Recently, I found out that the ZFS pool on a FreeBSD is running out of space. There is no option to clean up this storage, but there are spare disks. So the next logical thing to do is to add 2 extra disks to the existing (mirror) ZFS pool. This FreeBSD server is a virtual machine (VM), and after attaching 2 physical disks to this VM, I had difficulty identifying these disks....

I have a Void linux VM which only gets turned on once in every month. Today, when I booted up and updated the packages on this VM, I noticed that there are many old kernels installed. As a seasonal Void user, I had no clue on how to remove older kernels. Fortunately, a quick Google search pointed me to a video: VOID Linux: Removing old kernels with vkpurge. Basically, Void comes with a pre-installed utility program called vkpurge....

If you’re familiar with Kerberos, one way to check if a ticket is valid is to run klist command. ❯ klist Ticket cache: FILE:/tmp/krb5cc_1001 Default principal: username@UNIVERSITY.EDU.AU Valid starting Expires Service principal 02/07/21 11:26:50 02/07/21 21:26:50 krbtgt/UNIVERSITY.EDU.AU@UNIVERSITY.EDU.AU renew until 03/07/21 11:26:50 02/07/21 12:24:07 02/07/21 21:26:50 cifs/server1.UNIVERSITY.edu.au@UNIVERSITY.EDU.AU 02/07/21 12:24:07 02/07/21 21:26:50 cifs/server1.UNIVERSITY.edu.au@UNIVERSITY.EDU.AU ❯ date Mon 05 Jul 2021 16:01:59 AEST From the above output, the principal ticket expired since 2 Jul. So how do we find out if the Kerberos (principal) ticket expires programmatically?...

Suppose you just connect a Raspberry Pi to your home network using ethernet interface, and the Pi is not connected to a display device. How would you find an IP of that Raspberry Pi? Well, you’re right…whatever you say. There are a few ways to do this - looking at DHCP log, router log, …etc. But here is an even easier way to achieve this - using a command line tool called nmap....

I just updated my Foreman server and reboot, then this happened when I accessed the web console: Service unavailable ERF64-6496 [Foreman::MaintenanceException]: There are migrations pending in the system. This was the first time I’ve seen this message, and possibly because I haven’t done the update frequently enough. Fortunately, according to this blog post, it should be relatively easy to fix. [root@foreman ~]# sudo foreman-rake db:migrate API controllers newer than Apipie cache!...

If you use LVM frequently enough, especially when re-using existing disks, you might come a cross a problem when you’re unable to create a physical volume from that disk. For example, here is what I encountered today when I tried to create a physical volume on a device called /dev/sdb. [root@db3 ~]# pvcreate /dev/sdb Device /dev/sdb excluded by a filter. I’m sure I haven’t had any filters in /etc/lvm/lvm.conf. To fix this, I needed to wipe the signature from this device with wipefs command....