Table of Contents
Useful Commands for Windows Subsystem for Linux
wsl -l -v - check current WSL version in use
wsl -–set-default-version 1 - set default WSL version. Currently 1 or 2.
wsl -–set-version Ubuntu-20.04 2 - convert WSL version to version 2 where Ubuntu-20.04 is the name of the distribution.
Upgrade/Install PHP 7.4 in CentOS 8
The good news is this whole process is relatively painless, so here we go.
As always, all the commands assume you have root permissions.
Install the EPEL and remi repositories.
dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm dnf install https://rpms.remirepo.net/enterprise/remi-release-8.rpm
List the PHP versions you have available
dnf module list php
This should list versions of PHP both in the main repositorys as well as the remi repository. We want to enable remi-7.4.
Reset the php module (if you already have an existing PHP version installed)
dnf module reset php
Install PHP 7.4
dnf module enable php:remi-7.4
Update using dnf
dnf update
PHP 7.4 should now be installed.
Verify PHP version
php -v
Set up unattended-upgrades on Ubuntu 20.04
Package upgrades can be set up to install updates on Ubuntu without user intervention.
Install unattended-upgrades
apt install unattended-upgrades
Install mailx
apt install bsd-mailx
This will install also install Postfix. mailx is what unattended upgrades uses to send external mail.
Configure unattended-upgrades
Edit /etc/apt/apt.conf.d/50unattended-upgrades. This file is mostly self explanatory. The options can be enabled by deleting un-commenting the line. At the very least, configure the following:
Unattended-Upgrade::Mail “your@email.com”;to allow sending notifications to your e-mail address.Unattended-Upgrade::Automatic-Reboot “true”;to enable auto-rebootsUnattended-Upgrade::Remove-Unused-Kernel-Packages “true”;to remove kernel-related packages. This is usually done usingapt autoremove.Unattended-Upgrade::Remove-New-Unused-Dependencies “true”;- remove unneeded dependancies. Also manually done withapt autoremove.Unattended-Upgrade::Remove-Unused-Dependencies “false”;- remove unused packages, also,apt autoremove.
Restart unattended-upgrades
systemctl restart unattended-upgrades
Configure Postfix
Edit /etc/postfix/main.cf. Configuration of postfix is outside the scope of this article. For my purposes, I use a relay, so I edit and uncomment relayhost = to point to my relay.
Test mail
mailx -vvv -s "Subject" your@e-mail.com
Press CTRL D to send the email.
Test your set up
unattended-upgrades --dry-run -–debug
Quick time server set up on HP/Aruba switches
This is a quick configuration of setting a time server on Aruba/HP switches.
Enable sntp
timesync sntp
Specify how to get to your time server
sntp unicast
If your DHCP server specifies an SNTP server in it's leases, then you didn't really have to go through this.
Specify the time server
sntp server priority 1 IP.IP.IP.IP
Replace IP.IP.IP.IP with your server IP.
Set timezone
time timezone -360
Set this to for your location.
Set daylight-savings time rule
time daylight-time-rule continental-us-and-canada
Set this to for your location.
Verify your changes
show sntp
Fix software updates in Cockpit in Ubuntu 20.04
Software updates on the Ubuntu system will fail because Cockpit on Ubuntu doesn't detect a network connection. To fix this, you must use NetworkManager instead of the default networkd.
You need to be root or sudo root for all these commands. Edit your netplan file in /etc/netplan and add the following two lines under network:.
version: 2 renderer: NetworkManager
Remember that spaces matter in YAML files.
You will then need install network-manager.
apt install network-manager
Disable networkd.
systemctl disable systemd-networkd
Enable NetworkManager
systemctl enable network-manager
Apply your new settings
netplan apply
Profit!