topic Re: What is exactly creating an alias of interfaces? in Firewall and Security Management

What is exactly creating an alias of interfaces?

Blason_R — Tue, 25 Jan 2022 03:55:56 GMT

Hi Team,

Just wondering creating an alias interface means creating a sub-interface in CISCO? Will it carry the traffic for sub-interfaces if so?

e.g. on Bond20 Physical IP is 192.168.10.20/24 and alias created is 10.10.10.20/24. In that case if 192.168.10.x and 10.10.10.x is on same swtich with default vlan will they able to communicate through firewall?

Re: What is exactly creating an alias of interfaces?

_Val_ — Thu, 27 Jan 2022 09:25:50 GMT

Basically, yes

Re: What is exactly creating an alias of interfaces?

Blason_R — Fri, 28 Jan 2022 06:22:30 GMT

Now I tried adding Alias on Interface eth0 and tried pulling in topology it did not appear as a sub-interface. I believe it should appear there right?

Re: What is exactly creating an alias of interfaces?

Danny — Fri, 28 Jan 2022 07:23:54 GMT

sk89980 - Support for Sub-interfaces / Alias IP address / Secondary IP address in Check Point products

Re: What is exactly creating an alias of interfaces?

Chris_Atkinson — Fri, 28 Jan 2022 09:44:28 GMT

If the default VLAN is 2 for example you might get away with bond0 and bond0.2 both having IPs if you're lucky (depending upon how the switch handles your tagged and untagged frames) but I'd suggest you go about fixing the design that requires this in the first place...

Re: What is exactly creating an alias of interfaces?

Chris_Atkinson — Fri, 28 Jan 2022 09:45:32 GMT

On the Cisco side are you using different VLANs or secondary IPs as they serve seperate purposes?

(Again secondary IPs from a design perspective are sub-optimal)

Re: What is exactly creating an alias of interfaces?

Blason_R — Fri, 28 Jan 2022 08:04:15 GMT

Right - With Vlan there is no issue since I can create multiple however I have maestro device where I need to create around 20 sub-interfaces as previously network was terminated on Router where those sub-interfaces are defined without vlan.

Re: What is exactly creating an alias of interfaces?

Chris_Atkinson — Fri, 28 Jan 2022 09:46:46 GMT

@Blason_R wrote:

Right - With Vlan there is no issue since I can create multiple however I have maestro device where I need to create around 20 sub-interfaces as previously network was terminated on Router where those sub-interfaces are defined without vlan.

I can't speak to the upper limit that are supported but to achieve this (Aliases) on Maestro please see sk167073.

If it doesn't work as advertised you should contact TAC.