WAN1 and WAN2 same subnet

Netwow
Building a reputation

WAN1 and WAN2 same subnet

Is it possible to configure both WAN uplinks on an MX 450 in the same public subnet?

15 REPLIES 15
MRCUR
Kind of a big deal

While I have never tried this, I believe the MX will accept this config. I am curious what you're trying to achieve from this however as it doesn't sound like you'll really gain any availability from this setup. 

MRCUR | CMNO #12
Netwow
Building a reputation

We want the ability to load balance across the to 2 WAN ports with only one provider. 

MRCUR
Kind of a big deal

Do you have higher than 1Gb or 10Gb bandwidth from the single provider? 

MRCUR | CMNO #12
Netwow
Building a reputation

Yes I do. 

MRCUR
Kind of a big deal

The MX450 is only rated for 6Gbps currently FWIW. 

MRCUR | CMNO #12
Netwow
Building a reputation

Yes but I need to load balance across those ports. 

jdsilva
Kind of a big deal

@Netwow you can do what you're asking. But given the info you've supplied it doesn't make sense from a design perspective. Just because you can do something doesn't always mean you should. I would encourage you to review your design and decide if this sort of setup really satisfies the requirements you have.

Vince-D
Conversationalist

Is the gateway address the same on both connections?

Netwow
Building a reputation

Further explanation:

 

The MX has a throughput of 6 gig. The 2 uplink ports are rated at 10 gig. Yes I understand this is 6 gig stateful. 

Both WAN 1 and Wan 2 are connected to 10 gig ports on the ISP router. I want to load balance across WAN1 and WAN2 at 3 gigs. Yes on the same gateway. 

Netwow
Building a reputation

yes we have a 10 gig from the provider

MRCUR
Kind of a big deal


@Netwow wrote:

yes we have a 10 gig from the provider


If you're paying for a 10Gb pipe from your provider, wouldn't you want a firewall that can handle 10Gb then? 

MRCUR | CMNO #12

If each WAN port is getting its own public IP, I don't see why this wouldn't work. Its not truly redundant, but it should work for aggregation. 

 

 

I have a an MX84 that is ultimately doing something theoretically similar, but not for the purpose of aggregation. 

 

The MX can do "private IP" routing on the LAN ports (like to an MPLS router for example), so if you don't need inspection and NAT, that could possibly be an option too. To my knowledge the default 0.0.0.0 has to go through the WAN ports though. 

 

T-800

jdsilva
Kind of a big deal

I was told by Joe Aronow this week it can be done. I thought I tried it and it didn't work but now I'm doubting myself...

akan33
Building a reputation

a network device shouldn't be allowing the same segment in two different interfaces right, is that true that the MX allow it? 

MRCUR
Kind of a big deal


@akan33 wrote:

a network device shouldn't be allowing the same segment in two different interfaces right, is that true that the MX allow it? 


It's not terribly uncommon for a firewall to have multiple interfaces in a network segment, especially on the WAN side. 

MRCUR | CMNO #12
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