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What are the main causes of downtime when using deployment slots in Azure App Service, and how can you minimize their impact on your application’s availability?

The causes of downtime when using deployment slots in Azure App Service are typically not related to the application loading process itself. Rather, downtime can occur due to a variety of factors, including misconfigured deployment settings, incorrect application code, and connectivity issues.

For example, if your application code contains errors or compatibility issues that were not detected during testing in the staging environment, these issues may cause the application to fail or behave unexpectedly when it is deployed to the production environment. In such cases, you may need to roll back to the previous version of your application code or troubleshoot and fix the issues before the application can be restored to normal operation.

Quick guide in how to setup access to a Draytek Vigor 130 through a Unifi Dream Machine Pro.

SSH into the UDM Pro:

ssh -oHostKeyAlgorithms=+ssh-rsa [email protected]

ip address add 192.168.2.2/24 dev eth7 ip route add 192.168.2.0/24 dev eth7

from the UDM Pro telnet to the Modem:

telnet 192.168.2.1

ip route add 192.168.0.0 255.255.255.0 192.168.2.2 static

Now you can use a web browser to access http://192.168.2.1/

Changes to the UnifiOS have meant that WAN ping does not work any more. You can enable this on the UDM by going into Firewall & Security in the UDM Network Settings. Create a new rule called “Echo Reply” in Internet Local and select “ICMP” for IPv4 Protocol and “Echo Reply” for IPv4 ICMP Type Name. Leave all other settings as default and ensure that Rule Applied shows “Before Predefined Rule”.

For a long time I have seen that Ubuntu APT has declared it has not got a stable CLI interface and with 22.04LTS that has become a thing. If you try to a automate apt -y upgrade after an update your command will never complete as it will pop up a dialog window asking you which services you want to restart. Not very friendly for automation.
Now I don’t know if this the right way to do it, but it works for me in my homelab. What we do is leverage unattended-upgrade and change the settings before and after we run this command. By default unattended-upgrade is set only to apply security updates, something you want right. However, when you are creating a template usually you want all the other updates and patches that go with the default setup of your distro. So this is how I do it under packer with a shell script:

$spec = New-Object VMware.Vim.VirtualMachineConfigSpec
$spec.memoryReservationLockedToMax = $false
$spec.memoryAllocation = New-Object VMware.Vim.ResourceAllocationInfo
$spec.memoryAllocation.Reservation = 0
Get-VM | Get-View -Property Config.MemoryAllocation | %{$_.ReconfigVM_Task($spec)}

If you have an encrypted OPNsense configuration file then you can use the following to decrypt it. Note no password has been defined, add yours as required:

cat config.xml.aes | grep -Ev 'config.xml|:' | base64 -d | openssl enc -d -aes-256-cbc -out config.xml -pass pass: -salt -md sha512 -pbkdf2 -iter 100000

pvcreate /dev/sdb  
lvmdiskscan -l  
vgextend ubuntu-vg /dev/sdb  
lvm lvextend -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv  
resize2fs -p /dev/mapper/ubuntu--vg-ubuntu--lv  
df -h

The Dell version of VMware has been released and can be installed simply on a standalone ESXi server once it is maintenance mode.

First get the ZIP file from VMware:

https://customerconnect.vmware.com/downloads/details?downloadGroup=OEM-ESXI70U3-DELLEMC&productId=974

You should verify the checksum:

MD5SUM:

b9db1e378bc0cfccd979fe0660867641

SHA1SUM:

9f5121f0d9d39aa32c0d3f71c13e117bf4923737

SHA256SUM:

c9a0025d0946ab154520d6606a50b5dca0218294e90250bd5a9a8a6dd4dee50c

Checksums for ESXi ZIP file

Upload the ZIP file to a datastore that can be accessed by ESXi (local or remote) however don’t copy it to the boot media unless you know what you are doing.

Option a command prompt as Administrator.

wsl --install

Then reboot and open WSL to complete the installation. That is it, install Ubuntu 20.04 LTS by default.

cp -f /etc/xrdp/xrdp.ini /etc/xrdp/xrdp.ini.org
cp -f /etc/xrdp/sesman.ini /etc/xrdp/sesman.ini.org
sed -i "s/autorun=/autorun=Xorg/g" /etc/xrdp/xrdp.ini
sed -i "0,/allow\_channels=true/{s/allow\_channels=true/allow\_channels=false/}" /etc/xrdp/xrdp.ini
echo "PREFERRED=gnome-session" > /etc/sysconfig/desktop
echo "unset DBUS\_SESSION\_BUS\_ADDRESS; gnome-session" >> /etc/sysconfig/desktop
echo "allowed\_users=anybody" > /etc/X11/Xwrapper.config
sed -i "/param=96/ a param=-AcceptCutText=0\\nparam=-SendCutText=0\\nparam=-SendPrimary=0\\nparam=-SetPrimary=0" /etc/xrdp/sesman.ini
systemctl restart xrdp