WAN Fails Periodically on TZ 350
I have a SonicWall TZ 350.
The set up is pretty simple. I took the defaults for configuring the WAN side putting in my static public IP address and using 8.8.8.8 and 8.8.4.4 as my DNS.
Anywhere between 5-7 times per day for 15 minutes at a stretch, access to the internet fails for all the computers on the LAN. They can get to each other but not to the internet.
When I ping the public IP address through the SonicWall during these internet failures, the pings fail but the firewall is showing the interface (X1) as up.
Can someone provide me some guidance on what the next debugging step is, I would really appreciate it.
Answers
Does the same occur with a different device? Have you contacted your ISP?
Hi @NEKTON,
Thank you for visiting SonicWall Community.
During the issue time, please initiate a ping to the SonicWall's WAN gateway from the LAN PC and also from the SonicWall GUI. This would tell if the issue exists between SonicWall and its WAN gateway.
Possibly below KB article can help you.
Regards
Saravanan V
Technical Support Advisor - Premier Services
Professional Services
The TZ 350 is connected to a dumb switch. There is also a TZ 500 from a different company connected to the dumb switch. The dumb switch is connected to a router that goes out to the internet. There are no internet connectivity issues with the computers connected to the TZ 500.
I am able to connect to the LAN side of the TZ 350 but pinging the WAN gateway of the TZ 350 and the router fails. Pinging the IP address of the router does not fail. As I mentioned everyone on the TZ 500 continues to have internet access.
Have you contacted your ISP? Is the ISP providing more than one static IP address on the circuit? You haven't given us much information...
Hi @NEKTON,
Sounds to me like an issue on the upstream of the TZ 350. Connect the ISP router directly to the TZ 350 box just to rule out looping at the switch level if any and check the Internet access via TZ 350.
Regards
Saravanan V
Technical Support Advisor - Premier Services
Professional Services
Thanks for your response and suggestion. I don't have control over the ISP router as that belongs to another company who is providing us use of the router. The router only has a single point of entry for multiple firewalls, hence the dumb switch that the TZ 350 and TZ 500 are plugged into. I did notice from a label on the ISP router that the broadcast address was 255.255.255.248 while what I was told to configure for the TZ 350 WAN was 255.255.255.240. Not sure if that would make a difference.
I am assuming they are providing multiple static IP addresses. As I mentioned in the comment above the TZ 500, router and TZ 350 all have public IP addresses. Unfortunately, I don't have access to the ISP as that is owned by the company that we are a subsidiary of. I can see what information I can gather from them. They set up the router and the TZ 500.
Hi @NEKTON,
Try changing the subnet mask after consulting the ISP once if possible. I feel that there is a 50/50 chance.
Regards
Saravanan V
Technical Support Advisor - Premier Services
Professional Services
I did change the subnet mask. That did not resolve the problem. It turns out there was a spare public IP address that the owners of the gateway had. I used that and the problem seems to be resolved. I was told the symptoms can be characteristic of an ARP conflict especially with the new IP address not having a problem, but don't really understand that if the original IP address I was given was not in use.