There are a couple of aspects to what the management interface definition actually does, let's cover the Multi-Queue side first.
In regards to Multi-Queue and the management interface, it was impossible to enable Multi-Queue on the defined management interface in the Gaia 3.10 FCS (First Customer Ship) edition of R80.30 and the FCS of R80.40 (which uses Gaia 3.10). The explanation I got from R&D is that they wanted to ensure management access to the box even if some kind of Multi-Queue failure occurred, as MQ is enabled by default on all interfaces that support it under Gaia 3.10 except the management interface.
This restriction was lifted in Gaia 3.10 R80.30 Jumbo HFA Take 219+ and R80.40 Jumbo HFA Take 78+. In R81+ FCS MQ is enabled by default on all interfaces that support it. I'm not exactly sure what happens to the MQ status of the management interface if you started with an older Jumbo HFA or FCS and cross the boundary into where MQ is supported on the management interface, I believe it does get automatically enabled.
Be warned however that it is not a good idea to manually mess around with MQ's state on the various interfaces under Gaia 3.10 as you can end up with various issues such as sk168498: High rate of input discards after reboot when Multi-Queue is configured and sk167200: Multi-queue state is "off" when changing the management interface.
The other aspect to the management interface definition independent of Multi-Queue is what the definition means to the Gaia OS:
- The defined management interface will have it's IP mapped to the firewall's hostname in the /etc/hosts file generated at Gaia boot. Elements of the Gaia OS (not Check Point Product code) that need to determine what the main IP is they should use for various purposes will look here.
- Trying to change the IP address of the management interface in the Gaia web interface will throw a warning cautioning that completing this change may cut off your administrative access.
That's about it as far as I know, if I missed any other impacts I'd love to hear about it. The management interface definition does not impact or restrict your ability to "manage" the Gaia OS with SSH or HTTPS on any interface, as long as the firewall policy and the Gaia "Authorized Hosts" definitions (clish command add allowed-hosts) permit it. As far as which interface to choose as the management interface, I did provide some guidance on this in my Gaia 3.10 Immersion video course; here are the relevant pages:
Gaia 3.10 Immersion Video Course Page 64Gaia 3.10 Immersion Video Course Page 65
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