I have a new Balance 20x running v8.3.0 firmware with a pretty much OOB config other than setting up the WAN connection and added SSID. I have 2 devices (Laptop and Raspberry Pi) on the same SSID and can’t get to the Pi web server from the laptop.
I can see both devices connected to the Balance 20x SSID. Both can communicate to the Internet over WAN connection. If I connect the Pi to the Balance 20x ethernet LAN port, I can get to it from the Laptop that is still on the WiFi SSID, but not if the Pi is on WiFi, connected to same SSID.
That made me think it is something like a WiFi Guest Mode that is blocking layer 2 between WiFi clients. So then I dug into AP > Wireless SSID > SSID settings and don’t see anything that should be blocking communication between devices on the same WiFi SSID. VLAN is set to ‘Untagged VLAN’. Under the “Guest Protect” section, ‘Block all private IP’ is unchecked. Both the Custom Subnet and Block Exception Networks are blank. Firewall Mode is set to ‘Disable’. Firewall is out of the box with only default rules. I don’t see anything that would prevent access.
Anyone have an idea what to check?
If you reboot the pi, does the wifi work for a few mins? Mine does something similar on a apo-ent. I think it’s the pi.
The Pi is working fine on WiFi. It maintains connection, have done multiple reboots. It always connects and stays connected. It is accessible from that Internet service both when connected via WiFi or ethernet. The Pi is running Victron Venus OS, acting as a Cerbo GX hub. It connects to Victron’s VRM servers and I can access its console over from the Internet Victron site, and see it regularly reporting in. If the Pi is plugged into Ethernet on the Balance 20x I can access it from my laptop that is on the Balance WiFi, but not from the laptop when the Pi is on the Balance WiFi (with laptop and Pi both on the same SSID). It appears it is something on Balance WiFi blocking. Going to try some sharing connection between two laptops either between ethernet or wifi on the Balance and see if get anything different.
It’s not the Pi. I just tried testing with 2 win10 laptops. With both connected to ethernet LAN, they see each other in Windows File Manager Network. Can also see each other when one is connected to WiFi and one to ethernet LAN. When both are connected to WiFi on same SSID, they can’t see each other. It’s like a WiFi Guest Mode, but do not see anything configured that way in the AP setup, unless I’m blind.
That’s weird. Just to confirm – you don’t have “Block all Private IP” checked as in the example below – right? (I know you said it’s not but maybe a double check for the pertinent SSID?) And, also to confirm, the clients are on the same subnet, right?
I triple checked, the Block all Private IP is unchecked, and clients are on same subnet. All are getting DHCP IPs of 192.168.1.x
I agree, it is very strange and has me befuddled.
Did some more testing. If I connect devices to the default out-of-the-box Peplink_XXXX SSID, I can get from device to device. But if I create another SSID, with exactly the same default settings as the OOB Peplink_XXXX SSID, I can’t communicate from device to device. Any ideas? Is this a bug in 8.3.0? I upgraded the firmware to the latest as soon as I got the Balance 20x, as I need some of the v8.3.0 features, so can’t say how it behaves on previous firmware versions.
I’ll invite comments from others. Maybe we both missed something obvious here. ;<) I will say that I just tested for the issue you’re having with a client’s B20X and the router performs as expected with FW 8.3.0. Idunno.
I would check the Layer 2 Isolation attribute of the problematic SSID. Also, does ping work even if web access to the Pi does not? And, try it with firmware 8.2. Great thing about Peplink is how easy it is to toggle between firmware versions 
We have a winner. I had no idea that Layer 2 Isolation setting was hiding under the advanced settings for the SSID config. Just had someone else point me that direction. Unchecked the Layer 2 isolation box and all is working now. Seems very odd that would be enabled by default yet hidden under the advanced settings.
It is indeed annoying how the Layer 2 isolation option is hidden by default.
