Cluster Member Server needs to be able to use a FQDN, not just IP for the Public field

[officialh1]

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Prerequisites

• Can you reproduce? YES
• Are you running the latest version of SoftEtherVPN? YES

SoftEther version: 5.02
Component: SERVER
Operating system: Windows
Architecture: 64 bit

[In case it's a computer with known specs, such as the Raspberry Pi, you can specify it omitting the details.]
Processor: Intel 13th Gen/Not significant

Description

This has become a problem with modern firewalls.

Firewalls way back would need IPs to unblock with ports
Firewalls yesterday would take FQDNs and look them up and allow them with specific ports
Firewalls today REQUIRE the FQDN to be in the request

Some IT Admins are okay with allowing entire IP to communicate, some insist on requiring a hostname.

This causes a situation in a cluster mode it will break and VPN will not establish (I have not tested with a single server). I need the Public IP to also allow a FQDN and the requests need to use the FQDN

Expected behavior:
[What you expected to happen]

Allow entry of a FQDN and instruct the client to use the same FQDN

Actual behavior:
[What actually happened]

Only Public IP is available

Steps to reproduce

Manage the VPN Server
Enter Clustering Configuration
Set to Cluster Member Server
[you can only set a Public IP, needs to also allow Public FQDN]

[officialh1]

For a test scenario, you can use pfSense (firewall for the client side) and only allow communication to the FQDNs set for the controller and cluster members.

(client location: VPN Client | pfSense)--(other network)--(VPN Server[vpn.domain.com]/Cluster Member[member.domain.com])

pfSense allows client to FQDNs (https://vpn.domain.com and https://member.domain.com)

In pfSense use Aliases to set up the hostnames to use, then you can use them (the aliases) in the Rules.

[officialh1]

Having looked at the code, this is likely harder than requested I am guessing. The IP is converted to int32?? then stored (at least in memory?) this way. Should a separate method be used or should it all just be converted to string?

Code files identified so far involved: Network.c, Pack.c, Admin.c, Server.c