sync interfaces going up and down (partially up)

[fabiofabio]

Hello,
this morning I replaced one of the two nodes in HA, the new one was configured and tested in a test environment and in fact now it has no problems. the problem occurs in the two interfaces (ETH4 and 5) that deal with the sync. these keep going up and down

from the smart console are partially up

ETH4 is set as secondary in sync while ETH5 is primary.
node 1 (the old one) restarted by itself when I attacked node 2 (new) and node 1 was not restarting for a year. at this moment node 1 is running and has no problems, but due to the problems on the interfaces there is no node 2 among the members of the HA

I read that I should broadcast the network cards to solve the problem but I don't want to, as it has worked so far. the problem shouldn't be here.

any suggestion?

thanks