default GW as a second hop

[Jaro]

Hello all, 

I have a one (stupid) question.

I have default gw in our infrastructure, on FW and before that firewall, there is a SW with VLAN, and I need add IP address to this VLAN due to some changes in our network, Now it will be by this way 

FW(IP)-----(SW-Vlan-IP)-----host(IP) -this host will have default gw of FW, is it okay?

Thank you

[Seb Rupik · Accepted solution]

Hi there,

You've two options:

1) Include a route on the host which directs traffic to the FW IP via the SW-VLAN SVI

2) Configure proxy ARP on the switch so that it ARPs for the FW IP

https://www.cisco.com/c/en/us/support/docs/ip/dynamic-address-allocation-resolution/13718-5.html

cheers,

Seb.

[Jaro]

Hello, 

Thanks for answer, so if I set default GW (FW) on host it is not enough, I have to make route or proxy ?

I need to do it because of Microsoft NLB on Nexus.

[Seb Rupik]

Yes, with just a default route set to forward traffic to the FW, the host will have no knowledge of how to reach the FW IP address in its routing table.

[paul driver]

Hello

If the switch is performing inter-vlan  routing (L3) then give the host a G/W address of the SW ip,

If the switch isnt performing inter-vlan  and all three are on the same network then give the host a G/W of the FW.

res

Paul

[Moses Fernandes]

FW(IP)-----(SW-Vlan-IP)-----host(IP) -this host will have default gw of FW, is it okay?

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Hello,

It will be nice if you mention the IP addresses of the devices involved in your setup (from start to end) Or at least what you intend them to be.

This will stop the experts from assuming things and start giving you the correct solution in shortest amount of time/replies.

And don't forget to mark helpful posts.

Regards,

Moses