Mellanox ConnectX / HP MT26448 - Multiple PFs not yet supported


New Member
Apr 14, 2016
I got a bunch of these Mellanox ConnectX HP branded MT26448 cards on eBay for use in a Proxmox cluster, and mostly they're fine. However, once every 3 - 5 reboots, they don't come up and we see the this in the logs:

I've found a few posts about this issue in various places, but none with a solution. I know these are popular cards here, so I thought I'd ask if anyone here has experienced this, and if they found a solution.

More info:
root@sb1:~# lspci | grep Mellanox
01:00.0 Ethernet controller: Mellanox Technologies MT26448 [ConnectX EN 10GigE, PCIe 2.0 5GT/s] (rev a0)

root@sb1:~# dmidecode -t 2
# dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 3.0 present.

Handle 0x0002, DMI type 2, 15 bytes
Base Board Information
    Manufacturer: MSI
    Product Name: B250M BAZOOKA (MS-7A70)
    Version: 1.0
    Serial Number: H716080452
    Asset Tag: Default string
        Board is a hosting board
        Board is replaceable
    Location In Chassis: Default string
    Chassis Handle: 0x0003
    Type: Motherboard
    Contained Object Handles: 0
When they do come up normally, dmesg output looks like this:
root@sb1:~# dmesg | grep mlx
[    0.892052] mlx4_core: Mellanox ConnectX core driver v4.0-0
[    0.892057] mlx4_core: Initializing 0000:01:00.0
[    4.597322] mlx4_core 0000:01:00.0: PCIe BW is different than device's capability
[    4.597323] mlx4_core 0000:01:00.0: PCIe link speed is 2.5GT/s, device supports 5.0GT/s
[    4.597324] mlx4_core 0000:01:00.0: PCIe link width is x8, device supports x8
[    4.621739] mlx4_en: Mellanox ConnectX HCA Ethernet driver v4.0-0
[    4.621806] mlx4_en 0000:01:00.0: UDP RSS is not supported on this device
[    4.621824] mlx4_en 0000:01:00.0: Activating port:1
[    4.621917] mlx4_en: 0000:01:00.0: Port 1: enabling only PFC DCB ops
[    4.623159] mlx4_en: 0000:01:00.0: Port 1: Using 4 TX rings
[    4.623160] mlx4_en: 0000:01:00.0: Port 1: Using 4 RX rings
[    4.623287] mlx4_en: 0000:01:00.0: Port 1: Initializing port
[    5.436650] mlx4_en 0000:01:00.0: Activating port:2
[    5.436686] mlx4_en: 0000:01:00.0: Port 2: enabling only PFC DCB ops
[    5.437496] mlx4_en: 0000:01:00.0: Port 2: Using 4 TX rings
[    5.437497] mlx4_en: 0000:01:00.0: Port 2: Using 4 RX rings
[    6.136744] mlx4_en: eth0: Link Up
[    6.137102] mlx4_en: 0000:01:00.0: Port 2: Initializing port
[    6.322781] mlx4_core 0000:01:00.0 enp1s0: renamed from eth0
[    6.839398] mlx4_en: enp1s0: Link Down
[    6.948461] mlx4_core 0000:01:00.0 enp1s0d1: renamed from eth0
[    7.540782] mlx4_en: enp1s0d1: Link Up
[    7.541078] mlx4_en: enp1s0: Link Up
[    7.541079] mlx4_en: enp1s0d1: Link Down
[    8.295956] mlx4_en: enp1s0: Steering Mode 0
[    8.852097] mlx4_en: enp1s0d1: Link Up
[ 7325.449436] mlx4_en: enp1s0d1: Steering Mode 0
Any suggestions, or are these just too old to bother with at this point? If so, what's a reliable cost effective alternative? It needs 2x 10G Ethernet ports.


Kaini Industries
Nov 20, 2016
the original connectX's are suuuuuper old

Connectx3 40gbE cards are about $35, and you can use a little QSFP to SFP+ adapter to run them at 10gbE

low profile bracket model - HP 649281-B21 Infiniband 10/40GB Dual Port Adapter Low Profile Bracket | eBay

a little more expensive for the full height model (or you can just buy the full height bracket seperately) - HP 656089-001 Infiniband 10/40GB DP NIC 649281-B21, Full Profile | eBay

adapters to SFP+ HP Mellanox 655874-B21 QSFP/SFP Adapters 886111656585 | eBay

make sure to flash them to the oem connectx3 full 40gbE firmware, lemme know if you need help with that

Optionally, if you don't think you'll ever need the 40gbE, you can buy the 10gbE only version and not need adapters


high profile: CX312A Mellanox ConnectX-3 EN Dual Port 10 Gigabit PCI-E3x8 Card MCX312A-XCBT | eBay
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New Member
Apr 14, 2016
Many thanks fohdesha for taking the time to detail all of the options, that's incredibly helpful. Looks like the 40 gbE HP cards (with high profile bracket in my case) are the way to go, along with the QSFP to SFP+ adapters (until I can get some 40 gbE switches).

I've seen guidance on flashing these cards here on the forum so I'll follow that first and post back if I get stuck. Cheers!