There was a frustrating issue with SIP on Spectrum a while back: https://www.reddit.com/r/networking/comments/tt4hwo/followup_on_spectrum_is_rate_limiting_voipsip/
There really isn't a good answer other than to keep squeaking till greased. On Tue, May 13, 2025 at 9:40 AM Andrew Plas via NANOG <[email protected]> wrote: > A good 10 years ago I had this issue with DMVPN on Cisco routers plugged > into Charter modems in bridge mode mysteriously dropping ESP. Some were > fine, some were terrible. I worked around the issue by sourcing the tunnel > from a loopback interface and enabling NAT so the tunnel was NAT-T using > udp/4500 instead of ESP. Magically, no more issues. I am surprised to > hear this is still an issue. Those sites are all Silverpeak SDWAN now with > the same modems and no issues- Silverpeak uses udp/12000. > > Andrew > > On Mon, May 12, 2025 at 7:54 PM Brendan Carlson via NANOG < > [email protected]> wrote: > > > Yeah, that's exactly what I have seen in the past. No esp packets coming > > back, they're dropped incoming when in bridge mode. I have had better > luck > > with a replacement modem sometimes. > > > > --Brendan > > > > On Mon, May 12, 2025, 17:41 Christopher Aloi via NANOG < > > [email protected]> wrote: > > > > > Thanks Eric and Brendan. Yes, this is specifically related to when we > > put > > > the rac2v1s in bridge mode and I bind one of the static public IP > > addresses > > > to my router. If I captured packets on my router I can see GRE packets > > > leaving my router destined for my data center, but I never see any of > the > > > return packets I send. They are being lost/dropped on the way back in. > > I > > > am up to 30 of these now. What I can't grock is why they come in at a > > rate > > > of ~5 every morning. If anyone has any contacts at Spectrum that might > > > listen, or a workaround, please let me know! > > > > > > On Mon, May 12, 2025 at 4:04 PM Eric C. Miller via NANOG < > > > [email protected]> wrote: > > > > > > > Sorry, no help from here per se, but I used to get into the same > > > situation > > > > with AT&T Uverse routers. It seemed to be an issue with the built-in > > > > stateful firewall of the DSL router. I was able to get around it by > > > having > > > > tunnels to multiple public IPs and rotating their usage with a script > > on > > > > our equipment. The problem seems to self-resolve after a reboot. Very > > > > frustrating when you pay for static IPs. > > > > > > > > Good luck! > > > > > > > > Eric > > > > ________________________________ > > > > From: Brendan Carlson via NANOG <[email protected]> > > > > Sent: Monday, May 12, 2025 3:20 PM > > > > To: North American Network Operators Group <[email protected]> > > > > Cc: Brendan Carlson <[email protected]> > > > > Subject: Re: Spectrum & GRE > > > > > > > > I've seen the same thing on those same models with them being in > bridge > > > > mode specifically. They generally have issues with gre and l2tp > > tunnels. > > > > > > > > On Mon, May 12, 2025 at 12:13 PM Christopher Aloi via NANOG < > > > > [email protected]> wrote: > > > > > > > > > Hey All, > > > > > > > > > > Hoping someone can lend a hand here. I have ~ 1k customers > running > > > GRE > > > > > tunnels back to me for VoIP. Over the last three weeks these > tunnels > > > > have > > > > > started to break at a rate of 3-5 per day. We've narrowed it down > to > > > > > customers using specific Spectrum routers (rac2v1s and rac2v2s). I > > am > > > > > still able to access the public IP but the tunnel drops and will > not > > > come > > > > > back up. The fix has been to reconfigure as VPN or have the CPE > > router > > > > > replaced with a rac2v1k. I have been unable to get anyone to > listen > > to > > > > me > > > > > at Spectrum as these accounts are owned by the customer and I can't > > > > prove a > > > > > systemic issue. I have a list of accounts that have been impacted. > > > Has > > > > > anyone else encountered this? Any contacts at Spectrum that might > > > listen > > > > > to me? I am fearing all of these tunnels will go down at some > point. > > > > > > > > > > Thanks, > > > > > > > > > > Chris > > > > > _______________________________________________ > > > > > NANOG mailing list > > > > > > > > > > > > > > > > > > > > https://lists.nanog.org/archives/list/[email protected]/message/Q344UTT7EK7AGJ3YY7OHJZZ7UBPZI63H/ > > > > > > > > > _______________________________________________ > > > > NANOG mailing list > > > > > > > > > > > > > > https://lists.nanog.org/archives/list/[email protected]/message/727V6TQH3LZ5M6XPFMWZUR52JEJ4YLB5/ > > > > _______________________________________________ > > > > NANOG mailing list > > > > > > > > > > > > > > https://lists.nanog.org/archives/list/[email protected]/message/Z7Z4YWCI4MKTOOXOLIYSJTVWNVGMKAE6/ > > > _______________________________________________ > > > NANOG mailing list > > > > > > > > > https://lists.nanog.org/archives/list/[email protected]/message/FHFYKLHGVYR7ZLTQ6GG7G3VAH4WQJMF5/ > > _______________________________________________ > > NANOG mailing list > > > > > https://lists.nanog.org/archives/list/[email protected]/message/NZGY4XEV43YPYNPHQYIZ2SIOEJWIXWAQ/ > _______________________________________________ > NANOG mailing list > > https://lists.nanog.org/archives/list/[email protected]/message/RUAHK5BGTDCLELV6DYGCX3O6AIPUQU3I/ _______________________________________________ NANOG mailing list https://lists.nanog.org/archives/list/[email protected]/message/OBHCYEOJZBZ7NPQ4VJTSXAHKRKE5MNUI/
