Host not responding ESXi 5.5 and HA messages

hi guys

Lately I've been troubleshooting an issue with ping lost for my ESXi Servers. Network people tested all and they say is not networking.

These two servers are in a blade center - ibm - and they HS23, having Emulex and Broadcom NICs (Emulex OneConnect 10Gb NIC (be3), Broadcom NetXtreme II BCM5709S 1000Base-SX). Servers firmware is up to date and NICs and driver for NICs were updated yesterday and the issue is the same... continue ping lost

and today and I found repetitive "host not responding messages" like every 2 - 3 hours

and a lot of these too HA related as you can see below?

Any idea what logs do I have to check? for the ping lost and HA issue?

thanks a lot