Can you ping both vmknics from another ESXi host?
Are you using Jumbo Frames?
Check if ARP resolution works for both the target IPs at the same time, e.g:
# esxcli network ip neighbor list
Neighbor Mac Address Vmknic Expiry State
----------- ----------------- ------ -------- -----
10.1.1.1 00:15:3b:ff:81:89 vmk0 1041 sec
[...]
Sniff traffic on a vmknic which doesn't work currently to see if there is any traffic at all:
# tcpdump-uw -i vmk1 -nn
tcpdump-uw: verbose output suppressed, use -v or -vv for full protocol decode
listening on vmk1, link-type EN10MB (Ethernet), capture size 96 bytes
[...]
Check which driver your NICs are running with, e.g.:
# ethtool -i vmnic5
driver: bnx2
version: 2.2.1l.v50.1
firmware-version: bc 1.9.6
bus-info: 0000:03:00.0
For your NC522 NIC, it should be the nx_nic driver. Check which driver version you're running, the latest one is 5.0.626:
https://my.vmware.com/group/vmware/details?downloadGroup=DT-ESXI5X-QLOGIC-NX_NIC-50626&productId=327
Also make sure the NIC firmware is up to date.