I've noticed that the default Network Security Group for CVO has an allowed incoming rule for Kerberos TCP 749. Can anyone articulate why this is please?
Port 749 is the default port used for the KDC administration daemon.
As mention before by @ttran, port 749 is used for the kdc (kerberos) administration daemon.
Here is a link to the networking requirements for CVO in Azure incase you were wondering all the ports that are used in the SG.
Let us know if you have any additional questions regarding CVO in Azure or cloud in general
Probably my ignorance but isn't that an outbound port?
It is both inbound and outbound. If you are using HA CVO then the inbound traffic will go through the Azure Load Balancer, which is why traffic from the Load Balancer should be open to any port/protocol.
Let me know if you have any further questions.
Just to be clear, it is possible for the KDC administration daemon to initiate inbound traffic over 749 to a CVO appliance? In what circumstances please?
Cloud Manager creates AWS security groups that include the inbound and outbound rules that the Connector and Cloud Volumes ONTAP need to operate successfully. Security group rules for AWS
For more information please visit the below link.
Can the configuration of AWS External Security Groups for CVO be changed?