WAN port flapping on TZ270 connecting to Cable Modem
I have a client running a TZ270 Firmware 7.0.1-5030-R2007 that is having the WAN port going down for a few seconds and then back up. This started several months ago after it had been working OK for about 3 months. I have replaced the CAT6 cable between the Cable modem and SonicWALL X1. I have tried X2 as the WAN port on the SonicWALL. I have had the ISP (Shaw Cable) Replace the modem but the issues persists. I was running an earlier version of the firmware before the issues started and upgrade to the latest version after the issue began during my troubleshooting process. I have taken the SonicWALL to my office and connected it to my network and do not see the same issues. I have tried SonicWALL tech support but they have been of no help. Any suggestions or ideas would be greatly appreciated. I have this same model working at other clients sites connected to the same kind of modem with the same ISP with no issues.
Hi @PaulKuefler ,
It seems electrical problems. can you check voltage regulation maybe electrical surge? If it is possible plug the everything on UPS.
I thought about that but wouldn't the entire box go down due to electrical issues? It only affects the WAN port. I also have another router plugged into the same Cable modem and it doesn't appear to suffer the same issue as the SonicWALL. Unfortunately I don't manage this other router so I can't look at its logs.
@PaulKuefler did you tried changing the Link Speed from Auto Negotiation to 1 Gbps or 100 Mbps to avoid any issues on that front?
Unless there's something new on the market that I haven't seen, a cable modem can only have one device connected to it. Even if it has multiple ethernet ports, they are used for link aggregation, not multiple devices. How are you connecting a firewall AND a router to a single cable modem?
as @PaulKuefler said, change the auto negation on x1 to 100mbit or 1gbit.
it is an Hitron cable modem with a 4 port switch that can operate in bridged mode or non bridge mode. I have tried both. We have had both the SonicWALL and Cisco router connected to the LAN ports on the Hitron modem and I have also put the Hitron modem into bridged mode and placed the Cisco router onto the LAN side of the SonicWALL. I see the port flapping in both cases.
Have you seen this issue before or is this just something to try?
Yes @PaulKuefler, I have seen these before on old switch or routers like old HP 2500 (only support 100mbit 15 years old switches.), and asus modem, as far as i remember.
The Hitron modem support 1 Gbe so do you think its the autosensing that that is causing the port flapping?
doesnt matter 1gbe support. some times it doesnt work auto negotiation brand to brand. actualy not only sonicwall but I have seen on the Cisco to cisco swtich auto negotiation
I can try this. I have a number of other clients with the same SoncWALL TZ270 connected to the same model of Hitron with out this issue though.
I have the same issue with my TZ270 at home on Spectrum Cable. At the moment I have reverted back to my Zyxel because every time I install my TZ270 it constantly drops the connection. I will try again and set the port to 100MB.
Did this got ever resolved for you? A customer got a TZ 270 yesterday, connected to a Arris Cable Modem (Vodafone) and since than we're experiencing port flapping on X1 (link down - 3 seconds - link up) in a random interval. The TZ 400 which was installed prior did not had any trouble at all. New patch cable already in place and we fixed the X1 to 1Gbps Full, does not seem to make a difference. The modem comes with 4 ethernet ports, but same outcome on any of them.
The traceLog shows for every link down/up the following entries, can't tell if this is related to the cause or just the result of the flapping.
Quick follow-up, since connecting the X1 interface to a mini switch and from there to the modem the X1 interface stopped flapping. Another test with a new batch of network cables is in progress, if the flapping returns it seems that the network interfaces are a bit picky.
A (probably) last follow-up, as a countercheck we removed the mini switch and connected the TZ 270 again directly with the modem and the port flapping returned. So I guess it's quite fair to say that the TZ is not playing well with others in some situations, never had this with the TZ 400 installed prior. Can't say if this is a 270 specific thing or affects other units as well.
Mini switch it is, then, I guess.
I've got a new TZ370 disconnecting and reconnecting the WAN port as well, with Shaw. I've also tried the new cable, new modem etc https://community.sonicwall.com/technology-and-support/discussion/3976/assistance-needed-connection-drops-on-x1-interface/p1?new=1
I'll have to insert a small switch between the Sonicwall and the modem as a test.
@rsenio since attaching the switch to X1 no complaints from the customer, the links was stable ever since. Hope this fixes your issue as well.
Experiencing the same issue at multiple location
TZ270's, Hitron Modems (Shaw)
X1 flaps on and off constantly requiring occasional reboot to fix.
I'll try putting a switch in front to see if it makes a difference, but can we get an escalation on this? Feels like modem firmware issue but everytime I call Sonicwall support about this we get nowhere just the usual (update your firmware, change your cables, we don't see anything wrong)
Worked like a charm for me as well. This is something Sonicwall needs to look into ASAP.
Thanks for all the comments. I now have a switch between the SonicWALL TZ270 WAN port and the Shaw Cable modem and do not see any flapping. Weird thing is that I don't see this issue at any other client sites.
I was wondering if the users who had this issue actually tried the hardcoded Speed and Duplex with the same result or if they just put in the switch?
@ODtz370 having fixed Speed/Duplex was the first thing to try without success for me, others IMHO tried this as well.
Maybe SNWL should add a mini switch for free with the TZ-series 😂
The problem is still there, just bought a TZ270 with SonicOS 7.0.1-5111-R4251 running behind a Vodafone Cable Modem which itself is working fine for years... 🙄
Simple question: You solved it by putting a normal GBit unmaganed switch between the modem and X1 as I understand, right?
Thanks and kind regards,
@SebastianS yes, just put a Switch between the TZ and the Vodafone Modem, a 15-20 EUR solution for an annoying problem.
Thanks for your quick response, @BWC I'll give this a try...