B24 good signal - poor network bandwidth

Hello, I have 2 brand new B24s connected approximately 400 feet apart with direct line of sight connecting an office building to a work area building with 1 PC. Signal strength and WiFi connection is good.

Running the B24 diagnostic tests from both sides show between 800-1000MB transfer rates. But when a workstation tries to access an application on the server across the PTP wireless, the connection times out and never loads. Pinging the server IP from the workstation shows 1ms response with timeouts every 5th or 6th attempt. Doing an Internet bandwidth speedtest shows a very slow download while the PCs in the office all show a fast download.

I am using the Mimosa PoE injectors that came with the B24s. I found that they are a bit finicky on getting a link from certain switches, and ended up using HP Gigabit switches on each end in order to get a link. The green Ethernet light on the back of the B24s blinks (not sure if it should be solid green, as the blue WiFi light also blinks).

Any idea what could be causing the B24s to transmit/receive the diagnostic data packets at normal/expected speeds, but passing network traffic at very slow speeds?

I don’t have much experience with Mimosa products - I set up a similar PTP wireless with 2 B5-Lites which went very well.

I have tested/replaced network cables with the same results. I’m suspecting the Mimosa PoE injectors may be the problem.

Any advice or guidance is greatly appreciated!

Thank you!

Mike

Blinking green means that there is traffic going across the interface and the interface is at 1G.
http://backhaul.help.mimosa.co/backhaul-troubleshooting-guide-external-led-indicators-b24

I’ve see stuff like this when an interface is having a lot of FCS errors and/or is stuck at a lower speed or half duplex.

What’s the speed of the interfaces on the B24s?

Are you doing anything special with VLANs? If not, try pinging the B24s and the switches along the way from the computer and see what you see. You might try to ping to/from the B24s around the network as well.

Thank you for your response William, and thanks for the tips! One B24 interface is showing at 1Gbit Full Duplex, and the other is showing at 100MB Full Duplex. They are both plugged into HP Gigabit switches. When I set the station’s interface to 1Gbit Full Duplex, the interface changes to “Link Down”.

While I am in the interface, the Access Point radio (that was listed as 1Gbit Full Duplex) just went offline. So I simultaneously lost connection to the Station radio too.

I previously tested the cabling as part of this troubleshooting process, and they all passed.

I’m thinking I will swap the Mimosa PoE injectors when I am there tomorrow and see if the Access Point radio negotiates a 100MB Full Duplex link instead of the 1Gbit Full Duplex link (and visa versa on the station side).

No, I’m not doing anything with VLANs - everything is on the default VLAN 1. The purpose of this PTP wireless is to get a PC onto their network in a separate work/garage building so they can access an application on the server.

Thanks again for your help! If there is anything else you can think of for me to check, please let me know. I’ll report back tomorrow on switching the Mimosa PoE injectors.

Have a great night!

Mike

Cabling and ends are the big places to look.

Could be a bad injector, but I have not had any of those that are bad or have gone bad on me. Don’t forget to check your patch cables I have more then one of those be a trouble maker.

If you have a known good laptop (or really any device that can negotiate up to 1 Gbps) I would try plugging it in directly to the B24s and the switches and see if you isolate the issue.

You mention a HP switch, would you happen to be using any dynamic trucking features?

Make sure you are running the latest firmware on both radios.

This guide is pretty decent as well, (Note: I am using pretty good Cat5E cable just fine, but they do recommend Cat6 cable) Backhaul Troubleshooting Guide: Ethernet

Thanks again William - greatly appreciated! I tested all cables with a cable tester, and also swapped out the patch cables. When I go back onsite, I’ll bring a laptop and test everything as you suggested - thanks!

The HP switches are not using any dynamic trunking features. It’s a simple LAN of several PCs and a server.

Thanks too for the troubleshooting guide - I’ll go through those steps tomorrow. The patch cables from the PoE injector to the radios are Cat6 shielded (machine made). The patch cables from the PoE injector to the switch are Cat5e (not sure of the manufacturer - I’ll check, but there have never been any issues with any hardwired systems and they always auto-negotiate at 1Gbit).

I’ll also swap the PoE injectors to see if the issue follows the PoE injector, and will try more ping tests from other systems as you suggested.

Thanks again, as your suggestions and links are very helpful!

Mike

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Hi again,

We had a blizzard here and I was not able to continue troubleshooting this until today. I brought a multitude of machine-made Cat6 STP cables of varying lengths that all tested out on a cable tester. I also swapped the PoE injectors and network switches. No matter what I did the remote radio would only connect at 100Mbit. If I manually set the link speed to either 1000Mbit Full Duplex or 1000Mbit Half Duplex, the link would be listed in the GUI as “Link Down”, and the link light on both the radio and the switch would go dark.

I removed the remote dish and brought it up to the office area, and plugged it in to the same cables that the Access Point radio was using (and getting a 1000Mbit link). The remote radio would only get a 100Mbit link using the exact same equipment and cables.

I think this troubleshooting undoubtedly isolates this issue to the NIC in the problematic B24. Do I go through the distributor I purchased this kit from, or is there a different avenue to deal with Mimosa directly? I really need to get this link working as soon as possible.

Thank you for all of your help and suggestions - they are all greatly appreciated! I’m a newbie with Mimosa gear, as this is the second Mimosa kit I have worked with. Have a great night!

Mike

Make sure there’s nothing in the network cable socket that my be causing a problem with the pins. I’ve also seen, but not often, pins get bent and not make contact or short the pin next to them. Assuming everything checks out, then it sounds as if it’s time to call Mimosa support.

Thank you Wayne, I did check that and the pins look normal. I sent a message to the distributor I purchased them from, and ended up contacting Mimosa Support via chat. I detailed the troubleshooting steps I took, and they shipped out a replacement unit today. I am happy and very impressed with Mimosa’s Tech Support - they were great to deal with!

Thank you again William and Wayne for your help and suggestions! It is greatly appreciated!

Have a great night!

Mike

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