Balance 380 not passing DNS

Product Discussion Peplink Balance
1

This one has me stumped. We have a B380 at our home office running 7.02 2167. Two WAN sources. 100+ client devices, four PepVPN connections.

For the last few weeks all of a sudden the users cannot access the internet. During that period, the B380 shows traffic through both WAN ports.

I’ve done some testing and found that the B380 stops supplying DNS. If I try to ping a web site using either a client PC or from the B380 itself, I get no response. If I ping an external IP address, the ping replies again from either a client PC or the B380 interface.

All the LAN DNS options are checked:

  • DNS proxy is checked
  • DNS caching is checked
  • Public DNS records included is checked

When this happens the only solution is to reboot the B380. Thats very odd, as I’ve found Peplink devices very stable. Other than power failures we never reboot our Peplink routers.

For the moment I"m going to try running 7.0.1 firmware and see if the problem goes away. Have you seen this issue elsewhere?

1 Like
2

Just curious what public DNS servers you have on the WAN interfaces. Are they the same for both WANs?

1 Like
3

Each internet provider has its own DNS numbers. Same settings we have used for years. I have turned on remote assistance for you.

1825-285A-BB55

4

Thank you Don, we will investigate the issue.

1 Like
5

Upon initial investigation I see certain LAN clients have active sessions to public DNS servers. This tells me the DNS proxy is not being used by those clients but instead they are using public DNS servers other than the ISP’s.

Do you know if all LAN clients had this issue or only LAN clients using the DNS proxy? It would be helpful to get additional information to help narrow this down. You can open a ticket with us here if you want.

1 Like
6

When the problem occurs it affects all LAN clients, which can be over 100 devices.

I looked at the sessions log now, and see there is only one device that has sessions to public DNS servers. That device is a separate Meraki wifi system for customers. The Meraki system tracks customers elsewhere. It is interesting that devices connected to the Meraki wifi did not stop working. That supports my concern that the B380 stopped resolving DNS.

All our internal Peplink wifi devices, and hard wired LAN devices could not browse the internet (no DNS). We have a few devices such as VoIP which do not use domain names (they use IP numbers), and those devices did not fail.

The only way we could restore function is to reboot the B380. Not sure that proves the B380 was at fault. This has only happened three times in a two week period. We’re ok running 7.01 now but its only been a day since the last reboot, too soon to tell if that is a cure.

7

This helps to know how often it happened and the problem appears to be with the proxy. I will continue to investigate as we monitor with 7.0.1 firmware.

1 Like
8

Hi,

Actually this is the exact same thing happening to me and looking for a solution and came across this thread. Peplink Balance 380 with firmware: 6.1.3s2 build 1246.

We currently use it at a small residence with a single WAN source. About 100+ client devices as well over 20 APs.

This only started recently in about January and we generally have no problems with the Peplink hardware. Like mentioned before, the only solution to this is to reboot the router. When this occurs it affects everyone expect those that have manual DNS set on their machines (Google public DNS) and is not using the B380 for DNS relay.

Best Regards,
Minn Tun (Steven)

9

We have not seen this problem again since firmware 7.0.1.

1 Like
10

It looks like we’re having a similar issue. Under DHCP settings we have our Windows Server assigned as Primary DNS, however any client requesting DHCP receives our router’s IP as the DNS Server.

11

Hmm …:sweat_smile: Look like different problem as discussed in the previous post that is fixed in firmware version 7.0.1 and above.

  1. Can you provide screenshot for the DHCP server settings ?

  2. Command prompt : ipconfig /all for the IP address obtained ?

  3. Firmware version running for your device ?

1 Like
12

This would be expected. The client device receives the router’s IP as DNS server. The router actually gets DNS from the address you specified. This is necessary on a multi WAN environment. If you have different internet providers, you likely want DNS requests going out over each WAN, to pull from that internet provider’s DNS server. The Balance router acts as DNS proxy, pulling DNS from the WAN in use for the client’s session. If you only have one WAN, and have entered your WIndows Server as the DNS, then the router will get it from your Windows Server and pass the result to the client.

Some models can also cache DNS requests to prevent pulling the same request over and over. LAN > DNS Proxy > DNS Caching.

If you truly want the client device to pull DNS directly from your Windows Server, you would have to manually configure the PC client’s IP settings. If you are doing this simply to address your own LAN devices by name, you can enter them directly into the Balance LAN > DNS Proxy > Local DNS Records.

1 Like