Yet ANOTHER blown B5 Ethernet port

Another B5c blew an Ethernet port last night when there was a nearby thunderstorm (about 10Km away at the closest).

We follow ALL of Mimosa’s guidelines for Grounding, conditioned power, factory Cat6 cables etc etc… and yet if there is a lightning storm within 20 Km of a tower it’s a roll of the dice as to how many B5/C5’s will die.

This is a REALLY pathetic. I have 2 x 6 year old UBNT Rocket M5’s (which you couldn’t actually ground BTW) on that same tower and they are humming along, but I’m out YET ANOTHER B5c.

Will someone PLEASE FIX the Ethernet ports before I have to go back to UBNT?

I mean this is getting REALLY expensive and is annoying as Hell. Mimosa has a good product but this is really, really sad and ignoring it or blaming everything else is the worst thing Mimosa can do. FIX THE STUPID PORTS! I don’t care if you have to do a total channel recall. I’ve got ~$40K of your ‘carrier class equipment’ out there and I won’t be buying more. This is beyond ridiculous.

So that makes 8 x C5’s, 1 x C5c, 3 x B5’s and 2 x B5c’s that I’ve lost in the past 4 years. Comparatively I’ve lost 1 x 3.65 Nano, 2 x M900 Nanos, 1 x M900 Rocket, and that’s it.

So that’s 4 UBNT devices at about $700 CDN, VS 14 Mimosa devices worth about $4,700 CDN

Oh and I lost yet another C5 last week when the power went out and came back on blowing the Ethernet port.

Does anyone else see a problem here ?

Replying to myself because yet ANOTHER B5 has a flapping Ethernet port. The only recent storm - which was a good 20Km from this tower was the one that nuked the B5C above. Humidity is a bit on the high side and I have yet ANOTHER B5 that’s blowing chunks. Un-freaking-believable !

@Hector-M This is now WAY beyond ridiculous. I just spent another $1400 CDN on 2 more Mimosa B5’s just to replace these two pieces of junk… How does anyone make any money/provide a decent service with this equipment? I can’t see it ever happening.

I’m done. I’m going back to UBNT. The only Mimosa gear I’m buying for here out is to keep the crap I already have in the air working.

I’m going to start actively ripping it out. The only words I have to describe how angry I am at wasting >$40K on your equipment would get my post pulled.

I hope that someone else that is considering throwing away money on this gear reads this and goes someplace else. I’ve been running this business for 15 years and I’ve been in wireless for 10 beyond that. This kit is garbage and the standard reply is always the same and they won’t take responsibility for it. It’s not like this is the only equipment I have in the air but it IS the worst I have seen for reliability by a LONG SHOT.

Hey brother. I feel the same way. We ve lost about 8 c5s. We were frustrated too but the performance is what we need and get. Im fully confident thst Mimosa is and has been frustrated as well. I do believe they are trying to fix and will get it tackled; not because they give hoot but because its self preservation.

Give them time and give them the info they need. I need Mimosas to be great. We all need them to be great. Lets do this together and bust the slow wirless competitors out of the water.

Hello Ian,
I am sorry you are having a problem with your B5 link. Please let me know if you have contacted Support to address this issue. As I mentioned previously, Mimosa stands by the equipment we make, and we will work hard to make sure you are successful with it. We would like to work with you through one of our regular support channels to fix this issue and if necessary to replace the B5. You will receive a case number via email. Once you provide us with the serial number of the unit, we will be able to address the problem.
Thanks for your patience as we work to this problem.

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No argument about performance on the C5/c. When they work they can move traffic better than anything else I have deployed for PtMP, but a 30% or more failure rate after less than one year ? Add the CPE cost + Truck Roll + Helpdesk time + lost customers = At least $500 per CPE that dies in the field and I’ve lost at least 3 for every 10 I have deployed in just ONE YEAR!!!

There’s no business case that justifies that spend vs return.

The B5/C’s are more painful >$700 CDN per unit for a B5C - and then I have to pay climbers to replace it. A B5/C failure costs me $1,500 to $2,000 per end to fix, even more if it’s at the far end of the network, and they fail ALL the freaking time.

I ordered my first B5s as soon as they were announced. Right from day One Jamie blamed everyone else’s gear for Ethernet port flapping. It’s Cisco, it’s Mikrotik, it’s HP, it’s that power brick, it’s that type of cable. That should have been a red flag but, like you, I thought that it would get better. I NEEDed it to get better.

I’ve spent 10’s of thousands of dollars on their kit and at least 10K more replacing failed kit now and It hasn’t gotten better.

The only way that it MIGHT is when they lose customers and face up the fact that the Ethernet ports are crap and they need to fix them.

Hector - I’m having a problem with 4 x B5 Links. The two mentioned here and the one I spoke about a week ago and another one that was flapping last night.

It’s not just me: every ISP I know that has Mimosa’s kit out there says the same thing. They have a stack of very expensive door stops with Blown Ethernet ports and they are actively looking at other Vendors for options.

This is a CHRONIC problem with Mimosa’s equipment. You all know that but no one will admit it.

I’ll send support the Serial numbers but they are all at least a year old so I know you won’t be warrantying any of them.

So I’m stuck spending thousands of dollars to replace Mimosa radios with other Mimosa radios that I know will also fail in less than a couple years???

Nope. I’m done. There has to be a sustainable option out there and Mimosa is not it.

Good Response Hector but its a little mechanical. When we lose equipment it happens at the worst time, worst day, and worst situation. When you respond you need to convey that pain too like… " Id be pissed if that happened to me… Im livid… We are going to get to the bottom of this fast and heads will roll. You guys shouldnt have to deal with this crap. " Just saying…:slight_smile: Gotta let us know you love us a lot and want us to succeed. Think of who a wisp operator is. We dont wear button downs and wingtips. :slight_smile:

I find if we run very short runs on C5s they stand up better. We have lost a lot of c5s but i have to believe they will fix. Its the learning curve. Im betting the farm on mimosa.

C5 installs are:

Shielded Cat5 or Cat6 Cable from the C5 to the Mimosa NID. The NID itself is grounded to the house ground block - usually at the utility meter base. From the NID to the POE it’s another Shielded Cat5

A separate solid copper ground wire with crimp on lug runs from the Ground screw on the C5 (which is too short and hard to put back in place so they often end up losing it and watching it roll down the roof and into the grass in the yard where of course you will never find it) to the ground lug on the NID itself.

Most runs are probably less than 50’ before they get into the house. It doesn’t matter.

Having been on the Mimosa train since basically Day 1, I thought that they would fix it too - but the C5 is less than ~2 years old and it has the same Crappy Ethernet port problem that the B5/C’s have and they are a 5 year old product now. So ummm …

Must be my lucky Week for Mimosa Hardware… came back from break and see this on my dashboard. STILL ANOTHER B5C with a Flapping Ethernet port! I’ve lost count now. I think that’s 2 B5/C’s DEAD and 5 flapping? in the past 3 weeks ? WOW.

We can literally Slap Up a Cambium PtP on 280’ Hand made Ethernet cables and they sit at GigE for months no matter what. Or an AF24, or AF5xHD - same thing… they JUST WORK!

Yet I spend >$800 on a Mimosa Radio and it’s a total Crap shoot as to weather the Ethernet port is going to work, flap, or outright die after 1 day, 3 months or 1 year.

Oct 12 16:18:39 Port: link state changed to ‘down’ on port 1
Oct 12 16:18:39 STP: set port 1 to discarding
Oct 12 16:18:41 Port: link state changed to ‘up’ (1G) on port 1
Oct 12 16:18:41 STP: set port 1 to discarding
Oct 12 16:19:01 STP: set port 1 to learning
Oct 12 16:19:03 STP: set port 1 to forwarding
Oct 12 16:19:19 Port: link state changed to ‘down’ on port 1
Oct 12 16:19:19 STP: set port 1 to discarding
Oct 12 16:19:21 Port: link state changed to ‘up’ (1G) on port 1
Oct 12 16:19:21 STP: set port 1 to discarding
Oct 12 16:19:41 STP: set port 1 to learning
Oct 12 16:19:43 STP: set port 1 to forwarding
Oct 12 16:19:59 Port: link state changed to ‘down’ on port 1
Oct 12 16:19:59 STP: set port 1 to discarding
Oct 12 16:20:01 Port: link state changed to ‘up’ (1G) on port 1
Oct 12 16:20:01 STP: set port 1 to discarding
Oct 12 16:20:21 STP: set port 1 to learning
Oct 12 16:20:23 STP: set port 1 to forwarding
Oct 12 16:20:40 Port: link state changed to ‘down’ on port 1

Wow ian1, your luck is horrible. I have a dozen B5/B5c out there and have only had 2 die, 1 Ethernet and 1 total death in last 2 years. So I find them to be about the same reliable as other brands I’ve used. I’ll admit ubnt’s usually just die (or get viruses) and don’t have Ethernet issues.

Grounding C5 Tip----buy some eye crimp ons so you don’t have to take the screw completely out, just crimp one on the end of your grounding wire (which is way too big for the little screw Mimosa puts on—if not, you ground is not effective—use #10 or bigger) and slide it under the screw just a turn and a half out.

Anyone out there using Mimosa B11’s experiencing this? Do they also have the blown Ethernet port issue?

Mimosa does through a good party! I just finished a week at Wispapalooze. They announced a new C5 line to replace the C5 with more antenna options—Maybe someone from @Mimosa can get on here and say if the Ethernet port has been redesigned or improved in any way with the new models for ian1. I personally am not alarmed by this with the client radios, but it is a HUGE concern of mine looking forward to moving from my current B5 backhauls to something licensed.

Hi @Tim4,

In regards to the C5x, yes we have made many changes and improvements for Ethernet. We make improvements with every new piece of hardware we create!

@anthony3 are you using NIDs or other surge supression with your C5s? It’s a night and day difference with a NID, shielded cabling, and shielded ends because the built up ESD in the C5 actually has somewhere to go. I have send many folks use NIDs without the metal ends or without shielding completely. NIDs are worthless at that point – just fancy tech access points to reach the radio.

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I have 3 sets of B11s running with no issues. (besides overheating power supplies, but that was my boss’s fault, passive cooling a cabinet is hard) No B5s, we avoid 5 GHz backhaul as much as we can.

To be truthful though, we baby the hell out of all of our backhauls.

We have lost a few C5s in the last year of deployment, but our lighting is horrible and most of those are because the customer didn’t use a surge protector like we recommend or the surge protector was +5 years old. The rest of the lost C5s were due to severe hail or direct lighting strikes (customers replacing most everything electronic in their house.) I have not checked the numbers, but I think the numbers are pretty even between our Ubiquiti CPE and Mimosa CPE (though I have not replaced a C5c because of lighting yet…)

As far as NIDs, I thought that they were only for external access to the CPE… Always wondered why we were running wires to ground from them… LOL. When we found that the Mimosa NIDs worked just fine for Ubiquiti antennas we have been saving ourselves $2 per NID and have a much nicer device to work with. More room and a cover that is not easily misplaced, way better.

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@Tim4 : Unfortunately my luck is not “bad”; this is a VERY common problem with every WISP I know (12 + me) that has deployed Mimosa. And really it doesn’t matter if it’s a Dead short on the port or “just” a port that flaps for some random reason for some random amount of time The point is this should NEVER happen. And it’s been a problem since Day 1. Jamie ignored it and continues to. We bought the product, believed all the excuses that it was US that were the problem, followed all the whitepapers on how to make it not happen (surprise it STILL happens ALL the Time) and got shafted in the process.

I bought into that line of propoganda for the longest time and thought that Mimosa would fix it. Nope. They just ignore it and it keeps happening over and over and over again. I get a low quality product and they get premium quality price for it.

Not any longer. I’m deploying the AF5xHD. Higher throughput on the same gain antenna, $200 CDN less per end AND they have TWO Ethernet ports so if one does die I don’t have to toast a $800 radio, PLUS, of all the WISPs I’ve spoken to about the AF5xHD, NONE of them has mentioned random flapping ports.

Guys, if you are running sheilded CAT 5/6 up a tower and you are bloweinf ports then its the design fault. This cable was never designed for disperment of high voltages the sheildinv was for foreign noise and minor voltage radiation. The other problem is the design only having a foil shield and some with minor drain wires. The ground wire from the top to the earth ground should be a #2 tinned soild and terminated on a tinned bus bar and the minimum should be a stranded #6 from the B5 to bus bar and all connectors should be compression crimp ( not those DIY crimpers) with a two hole lug. If anyone here has ever been on a cell tower check out the bonding and grounding. The WISP industry has evolved to a broadcast design such as the cellular network but there has been no industry design/ standards for bonding and grounding for the WISP industry, the best method is for fiber transport and a seperate power cable (shielded) has anyone looked at Inscape switches for the tower top? The best company for power/ fiber cable hybrids is Rosenberger which designs for most cellular companies.

Just my two cents from 30 years in the communications industry

We have our B5s, B5C’s, and B24’s connected with grounds to our UBNT Edgeponts which are fed with Fiber and dc powered over stranded 12 awg wire. The Edgeponts have a great ground to attach to. And since the cat5 run is way shorter to the Edgepoint then all the way down the tower it helps greatly with lightning and static electricity. Be sure to get the EP-S16 if you do it’s the only real switch.


@jack6 I might not be up to Cell phone tower standards but we run #6 braided up the tower and we crimp onto that with the ground cable that runs to each B5. Each of those is #14 solid copper with soldered ring connector on the B5 ground ground screw. We check resistance from each chassis to the ground cable. I don’t rely on the cable shield for anything to do with grounding.

More to my point though - it’s not just blown ports - it’s the ports flapping for no apparent reason. Even with shielded factory cables these things just randomly flap. Sometimes they stop, and sometimes you replaced EVERYTHING to make them stop.

Why can I buy a UBNT radio at $100 USD less and it’ll run for a year or more without a problem but Mimosa’s on the same tower randomly flap and/or die for no reason ?

To me that’s not a tower/grounding design problem. That’s an equipment design/engineering/cheap component problem. One that has been ignored since the first day of the of B5 model.

I was wondering if you have any other tower mounted radios that are experiencing the same port issue or is it only the B5? What is the condition of the blown port, electrolysis, wet or carbon build up? The problem with long runs of POE in an out door environment is that they were never designed for long runs and exposure to moisture, electrolysis is due to poor grounding ( both side of the CAT cable, carbon is due to excessive power with poor contact on the pins. I would think ( could be wrong) that Mimosa would source the ports form one supplier for all products. It sounds like you have a decent ground but stranded wire for a long run up a tower creates resistance and when a power surge is applied it will find the least resistance to ground and any blockage will create a blow out of the wire, connector, etc and try to keep a minimum 12” bend radius’s because tight bends also create resistance.

lmk what you see in the blown ports, curious.

Jack Jimenez

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@Jack6 The only devices that routinely demonstrate this problem are Mimosa’s. I the cases above only the Mimosa’s on those towers were showing any port flap/dead short issue. Other than a very near or direct lightning strike we very rarely lose a radio. Except for Mimosa.

I am out of the office for a couple of weeks or I would post a picture, but the port on the latest B5 looks completely normal. The cable ends were dry and there was no sign of water in the RJ or cable itself. That unit was out of warranty so we cracked it and inside ‘looks’ fine as well.

Today there is yet another B5 showing a flapping port (1G/100Mbps/down/1G etc) on a different tower - that tower is owned by a rail way company and I have to pay their employees to do everything (they have their own full time riggers). So, it costs me much more money to address this Mimosa ‘feature’ at that site than typical but it demonstrates (to me at least) that it’s not my Riggers messing up the job.

Ian, thanks for the reply. I think discussions like this are benificial whether or not Mimosa is addressing the issue because the people in the field can get a hands on look at problems. The internal may or may not show damage just like a circuit board that get a static shock ( that the reason for shock bracelets) the damage may show up at a later time have you ever taken the defective unit to the ground and plugged back in with a shorter CAT cable and reboot? There was some issue awhile back with inadequate power to run some antenna due to length of cable ie if you need 20W of power and you have a 400’ run you will have a loss so at -48 and 20W you will need a minimum of 2.4 amps. The radio will work at first but over time will fail or run intermittent. A direct hit of lightning is not necessary to cause issue it is sometimes the influence from that or near by high voltage lines. The radio has a 6kv internal surge suppressor which requires adequate grounding so poor connections will not allow it to function properly so internal damage can occur but it may look like a port flapping or other erros because data cannot be processed.

Has anyone RMA’d a defective back to Mimosa and recieved a response?