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nargon
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Lost 3% ping (2 every 60)

Tue Aug 01, 2017 11:35 am

Hello everyone.
I present myself, I'm Jordi, and I've logged in to your forum so I have a problem. I am usually using products of your brand to make my networks.
They work almost always very well.

When networks require linking, however, they almost always use Ubiquiti material.
This is where I found a dysfunction, which I did not know if it was Mikrotik or Ubiquiti.

I found out that a client and network user had problems with Skype communications. Every minute had a small loss of communication.

I was watching it could be, as the installation was new and the internet provider too. Until then, this user had an ADSL connection with very little capacity (2Mbps) but had never had this problem.

Now, I have contracted an optical fiber and have a 100Mbps symmetrical connection.
In the attached diagram you can see the entire network, where we found the problem.

Image

As you can see there are two final customers that use the same fiber. Customers' routers (HAP AC lite) receive the internet signal for a VLAN generated by another RB750 r3 router, and collect a public IP for dhcp delivered by the provider.

The problem is that exactly every 60 seconds, 2 ping between the HAP and the RB750 are lost.

Image

After many tests I have verified that this does not happen if the ubiquiti antenna that makes BSU has a certain firmware. And so I've let them know the brand's technicians.

One of the other tests I have done is to replace a HAP router for a PC and in this case whoever is the ubiquitous antenna firmware, there is no loss of ping.

I understand that the problem is an incompatibility between the two brands, which is why I also show the problem to you. As I have done with the other company.

I think that is not the only time someone has commented on this kind of problem, just look at google "loss 3% ping mikrotik" to see that on other occasions someone has encountered similar problems.

Could it be a routers configuration problem?
 
p3rad0x
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 1:17 pm

Hi,

Did you check if there is any port flapping on the wireless links?

Its very hard to troubleshoot a problem like this on a bridged network.
There you go then you touched something ;-) : it only takes a change in wind direction to screw with your nat :-)
 
nargon
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 2:03 pm

more information

As you can see I do the ping between the client router and the BSU without using any VLAN.
The VLAN transports internet.
Internet ping (via VLAN) also fails in a way.

Well, I have disabled the VLAN of the client router, and I have clearly lost the internet, but I still can ping between the client's MT and the BSU.

With Vlan disabled, there is no ping error, everything works correctly.
Once I restart the VLAN, the problem once again appeared.
I do not know if that can clarify something about this error.
 
49er
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 2:06 pm

Do you also check the log in the device?
I have kind of same problem overhere and I see in the log many records about problably RSTP loop.
But till now I cant find any loop
but I see same pattern. like every minute a log record and packet loss
 
nargon
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 2:08 pm

This problem is also being addressed in the ubiquiti forum, in this post
https://community.ubnt.com/t5/airMAX-AC ... ight/false
The only solution for now is change BSU ubiquiti firmware to oldest possible, but is not acceptable for security and performance reasons.
 
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mrz
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 2:14 pm

Run packet sniffer on an interface. If ubiquiti sends back broadcasts on the same interface where it was received then RSTP will block the port considering it as a loop.
 
nargon
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 2:14 pm

Do you also check the log in the device?
I have kind of same problem overhere and I see in the log many records about problably RSTP loop.
But till now I cant find any loop
but I see same pattern. like every minute a log record and packet loss
I also tried an RSTP to none with the same result.
In the registry there is no information about anything that could be evidence ...
It seems to be something that is running every minute on the mikrotik or the radio link
 
Duduhandelman
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 5:26 pm

Are you monitoring the device via snmp or Dude
Maybe even a winbox that open can cause this.
Good luck.
 
nargon
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Re: Lost 3% ping (2 every 60)

Tue Aug 01, 2017 8:42 pm

SOLVED



No problem on new firmware for ubiquiti antennas.

Old firmware, 7.2.5 make a "firewall" that solves the problem, but...



Solution:



Disable on Mikrotik devices all interfaces with internet access in "discovery interfaces".

In my case, Vlans.





Explanation:

In my case, which I understand very particularly, the Fiber optic internet provider connects me directly to a hub where the rest of the customers in the same geographical area are located. It is like a simple hub where a DHCP server assigns public IP to each device that connects to it. Yes, if you have three computers connected to the bridge that the provider gives you, you have 3 dynamic public ips.

Therefore, all the noise that comes from optical fiber, I receive it from the MT of my clients.

So, for whatever reason, the mikrotik when searching for neighbors makes a mistake every minute.
Simply, by deactivating this search, the system no longer fails.

Firmware version 7.2.5, for some reason, blocks the noise from the optical fiber hub, which is why the MT is not "hanging" every minute.

I'm sorry for how long you've lost trying to understand what happened, but, really, my internet provider's configuration is not usual, and I had not commented at any time since I did not think it was the problem.

Thank you very much to all

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