while upgrading my lan and wan to 2.5gbit I connected the lan port to the new poe zyxel core switch and boom. Network down. Even the unifi ap needed a power cycle. I could bypass with a unifi 1gbit switch to keep it working. I tried it all to make the nic compatible, with all tunable but only these posts here saved me. The only problem was the i226-v firmware. Now working smoothely
OLD
[00:002:00:00]: Intel(R) Ethernet Controller I226-V
Vendor : 8086
Device : 125C
Subvendor : 8086
Subdevice : 0000
Revision : 4
LAN MAC : 5847CA7D759C
Alt MAC : 000000000000
SAN MAC : 000000000000
ETrackId : 80000303
SerialNumber : 5847CAFFFF7D759C
NVM Version : 2.23(2.17)
PBA : G23456-000
VPD status : Not set
VPD size : 0
NVM update : No config file entry
checksum : Valid
OROM update : No config file entry
CIVD : 0.0.0
EFI : 0.1.4, checksum None
—————-
NEW
[00:002:00:00]: Intel(R) Ethernet Controller I226-V
Vendor : 8086
Device : 125C
Subvendor : 8086
Subdevice : 0000
Revision : 4
LAN MAC : 5847CA7D759C
Alt MAC : 000000000000
SAN MAC : 000000000000
ETrackId : 80000422
SerialNumber : 5847CAFFFF7D759C
NVM Version : 2.50(2.32)
PBA : G23456-000
VPD status : Not set
VPD size : 0
NVM update : No config file entry
checksum : Valid
OROM update : No config file entry
CIVD : 0.0.0
EFI : 0.1.5, checksum None
minisforum nab9, 512 ssd, 16 ram, opnsense 26.1
PoE++ Switch XMG-105HP 6 Port
Ubiquiti U7 Pro-Max
OLD
[00:002:00:00]: Intel(R) Ethernet Controller I226-V
Vendor : 8086
Device : 125C
Subvendor : 8086
Subdevice : 0000
Revision : 4
LAN MAC : 5847CA7D759C
Alt MAC : 000000000000
SAN MAC : 000000000000
ETrackId : 80000303
SerialNumber : 5847CAFFFF7D759C
NVM Version : 2.23(2.17)
PBA : G23456-000
VPD status : Not set
VPD size : 0
NVM update : No config file entry
checksum : Valid
OROM update : No config file entry
CIVD : 0.0.0
EFI : 0.1.4, checksum None
—————-
NEW
[00:002:00:00]: Intel(R) Ethernet Controller I226-V
Vendor : 8086
Device : 125C
Subvendor : 8086
Subdevice : 0000
Revision : 4
LAN MAC : 5847CA7D759C
Alt MAC : 000000000000
SAN MAC : 000000000000
ETrackId : 80000422
SerialNumber : 5847CAFFFF7D759C
NVM Version : 2.50(2.32)
PBA : G23456-000
VPD status : Not set
VPD size : 0
NVM update : No config file entry
checksum : Valid
OROM update : No config file entry
CIVD : 0.0.0
EFI : 0.1.5, checksum None
minisforum nab9, 512 ssd, 16 ram, opnsense 26.1
PoE++ Switch XMG-105HP 6 Port
Ubiquiti U7 Pro-Max
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