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I think you're missing that it isn't a /29 handed off from the ISPs. If it were, sure, you can use a layer 2 to split the /29 into 2 handoffs. See above - it's a /31 from one ISP and a /30 from the other. 1 usable IP for the handoff from each ISP. The respective /29s are routed via those networks. To assign the /29s to the MX, you either need a layer 3 switch for each ISP or a layer 3 switch that can do VRFs - which I didn't think the MS350 could do, but was hopeful that someone smarter than me had a work around so I didn't have to go to a DC 3 states over to put in another switch.
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Thank you! That's what I suspected and posed to meraki support on Friday but they have yet to confirm.
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2 weeks ago
I guess the part about what you're saying that confuses me is that since the uplinks to the ISP (/31 and /30) are on different subnets than the routable /29s, then how can I do that with L2? I thought L3 would be needed to transverse subnets? Apologies for my diagram as I don't have visio on this tablet. Here's a drawing of my setup. I think my problem is the MS default static route which is 0.0.0.0/0 via 12.76.70.205
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2 weeks ago
In the drawing, are you suggesting that each ISP only gets connected to 1 MX? What's the point of the switch then? If I understand that correctly, that doesn't work for me. Requirements are for redundant firewalls with redundant ISPs.
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In the US, it's somewhat standard as of late, especially in smaller markets. I order 2-3 circuits a day for customers, almost always with a /29, and this is how they're being provisioned. That, and we used to be able to get multiple handoffs - no longer.
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2 weeks ago
The other ISP does the same, but with a /30 - that routes fine for me, but the static route on the MS is that /30. I'm not able to program 2 static routes because the subnets would overlap and I don't want to do a 0.0.0.0/1 to ISP1 and a 128.0.0.0/1 for ISP2 because that would defeat the whole purpose of having redundant ISPs
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2 weeks ago
Please elaborate - maybe I'm missing something? The ISP gives a single handoff with a .16/31 (.16 for their router, .17 for mine) and a routable .0/29. So I created an interface on the MS with the .17 address and another interface with the .0/29 I'm running the MX in HA mode with a VIP, so that requires 3 IP - on the .0/29 subnet. I gave my MS .1, MXA .2 MXB .3 and MX VIP .4
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2 weeks ago
I have 2 ISPs with a single handoff. Both have /29 attached. ISP1 to a /30 and ISP2 to a /31. I use HA MX105s at this location. I installed a MS350 and created an interface for ISP1 on the /30 and another on the /29. I assigned the ISP1 /29 to my MX pair on WAN1 and it works fine. On ISP2, I crated an interface for the /31 and another on the /29. I assigned the /29 to the MX pair as WAN2 and it fails. I can ping from the MX to either of the interfaces on the /31 but not beyond. I can ping from the MS to the ISP router on the /31 but not beyond. I suspect this is because my default static route is for ISP1. Is there any way on a MS350 to make this work or will I need a separate switch for each ISP? The ideal config would use ISP1 if traffic came from WAN1 on the HA MX pair and ISP2 if traffic came from WAN2 on the HA MX pair.
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Dec 20 2023
9:01 AM
Swapped out the MS220 for a MS350 and it works kinda sorta. MXA is up with the assigned address in the /29 but MXB says "not connected" even though I can see pings to it's assigned WAN interface on the pcap - it just doesn't respond.
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Nov 29 2023
5:26 PM
Sorry to drag up an old post, but I'm having the same issue with ATT and a single handoff but a HA pair of MX105. Since they're HA, is the only solution a layer 3 switch in front of the MX pair? This was my first inclination, and I tried first with a MS120 and now a MS220 but still struggling.
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