NMS CHANNEL_HISTORY TRANSFER FAILED/MIMO_EVENT ethernet link down

Hello. I have a link with two Mimosa B5c and at my logs i have this messages:

2020-03-29 18:26:07 (UTC +0000) root: MIMO_EVENT ethernet link down
2020-03-29 18:26:09 (UTC +0000) root: MIMO_EVENT ethernet link up (1000/Full)
2020-03-29 21:23:17 (UTC +0000) syslog: MIMO_EVENT AutoEverything: NMS CHANNEL_HISTORY TRANSFER FAILED
2020-03-30 11:42:42 (UTC +0000) root: MIMO_EVENT ethernet link down
2020-03-30 11:42:44 (UTC +0000) root: MIMO_EVENT ethernet link up (1000/Full)
2020-03-31 11:56:58 (UTC +0000) root: MIMO_EVENT ethernet link down
2020-03-31 11:56:58 (UTC +0000) root: MIMO_EVENT ethernet link up (1000/Full)
2020-03-31 13:12:01 (UTC +0000) syslog: MIMO_EVENT AutoEverything: NMS CHANNEL_HISTORY TRANSFER FAILED
2020-04-01 05:34:46 (UTC +0000) root: MIMO_EVENT ethernet link down
2020-04-01 05:34:48 (UTC +0000) root: MIMO_EVENT ethernet link up (1000/Full)
2020-04-01 09:29:06 (UTC +0000) root: MIMO_EVENT ethernet link down
2020-04-01 09:29:07 (UTC +0000) root: MIMO_EVENT ethernet link up (1000/Full)
2020-04-01 13:31:36 (UTC +0000) root: MIMO_EVENT Wireless disassociated
2020-04-01 13:31:52 (UTC +0000) root: MIMO_EVENT Wireless associated

Can you help and explain to me why do i have this messages ?
Why did i have linkdown at 2020-04-01 13:31:36?
What can i do in order to fix it?

So the link down messages mean that the communication over the Ethernet Cable stopped momentarily.

Normally I see stuff like this when there are issues with the Ethernet Cable itself or the ends, although it could possibly be the radio.

Your first step should be to check the cable and see if there are any visible signs of damage. If you find damage you should replace the cable. Next up, check your ends and make sure they are crimped well and everything looks good, bad ends are the most common issue I find when I go hunting for an Ethernet issue. (If you are unsure just redo the ends)

Next up is to look for issues that could bug the cabling, what kind of cable are you using? (Sheilded/Unsheilded, Cat5e/Cat6, etc) Are there any powerful transmitters in your area?

Then try moving to another port on your router/switch, see if that clears up the issue, sometimes a bad port on a switch can cause these issues.

Finally, you probably will want to try replacing the radio and RMA it if the issue clears up.

As far as the Wireless issues showing up in your log, you will have to post more details for me to be helpful. Link Length, RX/TX signals for both sides, is your path shot clear? Pictures of your channel and power and main dashboard can help a lot.