nanog mailing list archives
Artificial Juniper SRX limitations preventing IPv6 deployment (and sales)
From: Andrew Kirch via NANOG <nanog () lists nanog org>
Date: Sat, 1 Nov 2025 23:33:33 -0400
To those from Juniper, You are actively harming your own sales, and IPv6 deployment. On the SRX3xx line, Junos artificially limits update-router-advertisement to three downstream interfaces. In practice, that means the box will only automatically inject delegated IPv6 prefixes into RAs on three VLANs. This is not a hardware limit. This is not a throughput limit. This is not “the ASIC can’t handle it.” This is an arbitrary cap in software. Here is the operational problem: I have an SRX-340 acquired through Juniper, fully legitimate. It’s being used in my home. I have five VLANs: • management • desktops • servers • iot • guest On IPv4, this is trivial. Each VLAN is routable, each segment is isolated, everyone’s happy. On IPv6, because of this three-interface limit, I can only have automatic prefix delegation and router advertisements on three of those VLANs. After that, Junos just refuses the config. There is no documented way to extend it. There is no warning in the product literature that “this feature stops working at 3.” There is no published technical justification, in fact, I can't find anything published about this limit at all. The result is that I cannot deploy IPv6 cleanly across my entire network using Juniper’s intended/automated method. My choices are: • break my segmentation model to fit an undocumented limit, or • start doing manual RA gymnastics and scripting around Junos just to reach VLAN #4 and VLAN #5. Neither of those is what we should be calling “enterprise-ready IPv6.” It's not even "home-ready IPv6". It's embarrassing. One of the small branches where I installed an SRX-345 has over 40 vlans. We heavily segmented to protect the network from east-west movement, for compliance, and to prevent the spread of ransomware. This is exactly the kind of paper-cut that keeps corporate networks from rolling out IPv6 everywhere. It’s not that IPv6 is “hard.” It’s that Juniper quietly ship artificial restrictions and then make the fix “buy a bigger box that you otherwise don't need.” I for one am not buying it. If this is a licensing/commercial segmentation decision (“branch” products get three VLANs of working IPv6 and if you need more you’re supposed to move up-market and spend tens of thousands more), then please say that, on the record, so operators can plan accordingly (buy from another vendor) and so architects can see what they’re actually buying. If it’s not intentional product gating, then please remove the limit, and provide that to everyone who has bought an SRX-3xx. There is no technical reason an SRX-3xx should only be able to advertise delegated IPv6 prefixes on three VLANs. There are both hardware and software solutions that work as UTM firewalls for branch offices that don't have automatic limits. I am not beholden to Juniper, and I can/will buy other solutions if I have to. That is not helping IPv6 adoption. I opened a jcare ticket on it years ago, and got crickets, so now we're going to see if sunlight is the best disinfectant. I'm not your biggest customer but I've purchased well over $700,000 worth of Juniper gear and jcare. I'm asking that Juniper publicly commit to fixing this, because I assure you I can buy something else. Regards, Andrew Kirch AS401854 _______________________________________________ NANOG mailing list https://lists.nanog.org/archives/list/nanog () lists nanog org/message/Z2ZX77BK4KT72XH3W6NDM42PUZXZ6ECU/
Current thread:
- Artificial Juniper SRX limitations preventing IPv6 deployment (and sales) Andrew Kirch via NANOG (Nov 01)
- Re: Artificial Juniper SRX limitations preventing IPv6 deployment (and sales) Saku Ytti via NANOG (Nov 02)
- Re: Artificial Juniper SRX limitations preventing IPv6 deployment (and sales) Marco Moock via NANOG (Nov 02)
- Re: Artificial Juniper SRX limitations preventing IPv6 deployment (and sales) Saku Ytti via NANOG (Nov 02)
