Basic setup:

3 Windows 7 Pro PCs running SW2017 (one of which still has SW2016 just in case).

License Server was on one client but Best Practice seems to be to host it on a real server class machine.

Did the whole install on server (2012 R2 VM running on Dell T630 hardware (RAID5, dual PS, ....)), Modify licence to release it from client, attach it to Server, all looks good in Server License Manager App on server.  Used latest software version 2017 SP4.1.  Using approved AV software SEP SBE.  Changed Client License Manager to point to new location (25734@XYZ-VIRT) - get connection error starting SW on client PC.  Tried using 25734@192.168.0.2 (IPV4 address of XYZ-VIRT) - still fails.  Tried same drill on second client PC - fails.  Disabled firewall on server - fails.  Tried to disable Firewall on client - can't as SEP SBE claims to be controlling the client firewall, despite specific  SEP SBE settings saying it should NOT take over for Windows 7 built-in firewall.  Same clients can see file shares on same server VM.  "nbtstat -c" looks good.  Pings work using NB names but resolve to IPV6, not IPV4 addresses.

So....

Anybody using a 2012R2 VM to host SW2017 Server License Manager?  Seems to be supported, although the VM part isn't clearly covered in the system requirements.  Hard to believe SW hasn't heard that VMs are the way of the world circa 2017.

Whatever the firewall settings, if any, from wherever (native and/or SEP), would allow local IP addresses in the DHCP range to communicate but block access to local static IPs (e.g. the server) seems pretty unlikely/odd.  Review of SEP SBE rules shows no signs of active customization anyway.

Of course the IT guy who set it all up is long gone, no network documentation.