RouterOS Version: 2.9.43
Router Board: RB532
I have a problem and I need some help on what to do/try next. I will try to be as brief as possible, but it will be hard since this has been an ongoing issue for months now. The problem I am having is Packet Loss from a Mikrotik backbone at the top of two towers down to a switch at the base of the tower.
We have two towers out of about 20 that are having the exact same issue. Each tower has 2.4GHz using Mikrotiks, 900 using Canopy, and 5.7 backhauls using Mikrotik, one of the two towers has 5.7 Canopy. At almost all of our towers we are the only carrier of any type accept for a few. From what I can tell the only thing the two problematic towers have in common is high RF.
One of the towers has been seeing problems for a few months. The only thing significant that happened around the time it started was a second Cell phone company setup shop right below us. So now there are two cell phone companies, us, and the local ambulance service on this water tower. As I said, the problem started about the time the second phone company turned service on, we worked with their RF and tower engineers, they were very helpful, and even turned the equipment off for about 30 minutes so we could test. Even when they turned their equipment off we were still seeing the packet loss. So we had to rule them out as the cause….
The second tower, the problem started last month. The problem started when we switched from one Mikrotik handling all backbones and the customer AP on the same board. We swapped to one Mikrotik for each backhaul and one for the customers. The only thing on this tower other than us is a high powered FM station; we are about 30-40 feet below their antennas. It should be noted though we had a number of issues at the beginning when we first turned this tower up and we had to go through a lot of reengineering to get service stable.
Basically, I need some ideas on what we can try to stop our packet loss. My only guess at this point is the high RF environment at each location is wreaking havoc on our Ethernet or Mikrotik. Below I summarized everything we have tried, but I wanted to cut this message off at this point, because I’m sure some people have already left me. If anyone has dealt with high RF environments and have had similar problems please share some ideas so I can fix this problem. If you are interested in helping, please read below, I swear I have done just about everything at this point, but there is always more to do.
Thank You!
Brandon Toyzan
Technical Operations Manager
Mercury Network - Michigan/Wisconsin
First here is some more information describing the problem.
Only one Mikrotik, the main backhaul, has loss. On top of that, we only see the loss going one way (keep in mind pings are two way...). If I ping from our main router, to the customer AP on the tower, I see the loss. The loss can range from 2% on up to 10%, there is no pattern to the loss. Sometimes you won’t see loss for 5 minutes, other times you will see loss every 30 seconds for 5 minutes. This is not a loading issue, as we have much busier and bandwidth intensive towers in our network.
The only customers who notice any thing are bandwidth intensive businesses or VOIP customers; we get no other complaints from anyone else.
If we ping from the Mikrotik at the bottom of the tower up to the backhaul Mikrotik at the top of the tower we do NOT see loss. We do see the loss, pinging from the Mikrotik at the top of the tower down the Mikrotik at the bottom of the tower.
MAC pings reveal the same thing, loss going down the tower, but not back up.
We do not see any packet loss going from the bottom of the tower up to the Customer AP or the other backhaul on the tower. Also there is no packet loss up to our Motorola 900 or 5.7 equipment. But there is loss, when pinging from our central colo router over the backhaul to the Motorola equipment, just like each other piece of equipment. Unfortunately, at one tower the back-up backhaul is on a much longer loop, and response times are higher, so switching to that backhaul would be noticed even by our web browsing customers. The other tower, unfortunately we just repositioned the backhaul to a new tower that has not gone active, so moving over to that backhaul is not an option yet.
Here is a list of things we have tried, I have been keeping pretty good track of them and adding them to a list as we go. Little things may have been done in frustration and I may not have kept track of them. I will summarize each as best as I can. Almost all of the steps below have been done to both locations at this point.
1. Removed Gel filled outdoor Cat 5, replaced with Shielded Cat 5
2. Grounded Shielded Cable
3. Replaced 48 volt PoE multiple times
4. Replaced switch multiples times
5. Changed the switch brands we were using
6. Replaced Mikrotiks
7. Replaced Radio Cards
8. Added Ferrite Beads, tested with them, moved them around, up down, side to side….
9. Grounded Cable to grounding rod, instead of our grounded cabinet
10. Re-grounded Cabinet, moved grounding back to cabinet
11. Tested with other local services (Had Cell carrier turn off equipment, had ambulance service talk on their equipment).
12. Wrapped Electrical Tape around the metal poles that our Mikrotik outdoor enclosures are on.
13. Replaced the Back-haul antenna.
14. Moved the positioning of our cables from one leg of tower to another, moved cables as far away from other equipment as possible.
15. Upgraded Mikrotik OS multiple times, currently on at least 2.9.43, one ap has 2.9.45, but it is a losing battle and a waste of time to upgrade every week.
Thanks…look forward to ideas.
We did come up with one more today while I was writing this, if truly I don’t have packet loss to the other Mikrotik unit at the top, I’m just going to get longer Coax to run from the antenna over to the Mikrotik that doesn’t have packet loss.
Brandon