Open Port Check Tool

https://networkappers.com/tools/open-port-checker

 

https://www.yougetsignal.com/tools/open-ports/

An In-Depth Guide to iptables, the Linux Firewall

This is a great guide to iptables:

An In-Depth Guide to iptables, the Linux Firewall

Migration with Azure Migrate

 

https://azure.microsoft.com/en-us/services/azure-migrate/

https://azure.microsoft.com/en-us/resources/videos/migration-with-azure-migrate/