Mellanox 100G NIC은 Infiniband 와 Ethernet 겸용으로 사용할 수 있음
Infiniband 로 설정된 경우, 펌웨어 유틸리티를 통해 Ethernet 으로 변경한 후 이용


$ cat /etc/redhat-release
CentOS Linux release 7.6.1810 (Core)


# lspci | grep -i mel
82:00.0 Infiniband controller: Mellanox Technologies MT27800 Family [ConnectX-5]
82:00.1 Infiniband controller: Mellanox Technologies MT27800 Family [ConnectX-5]


$ sudo lspci -vv | grep Mel -A 150 | grep -iE 'Mel|PN'
10001:01:00.0 Infiniband controller: Mellanox Technologies MT27800 Family [ConnectX-5]
        Subsystem: Mellanox Technologies Device 0003
                        [PN] Part number: MCX555A-ECAT

(참고)
https://community.mellanox.com/s/article/howto-find-mellanox-adapter-type-and-firmware-driver-version--linux-x 
https://www.mellanox.com/support/firmware/identification


# 환경변수 확인 결과 한글로 나오는 경우
$ export | grep KR
declare -x LANG="ko_KR.UTF-8"
declare -x LC_ALL="ko_KR.UTF-8"

# 만약 위의 결과에서 LANG 이 KR 한국어로 되어있다면 영문으로 강제로 설정
# 안 그러면 드라이버 설치 스크립트가 에러 남

# 환경변수 영어로 설정
$ export LANG=en_US.UTF-8
$ export LC_ALL=en_US.UTF-8



wget http://www.mellanox.com/downloads/ofed/MLNX_EN-4.7-3.2.9.0/mlnx-en-4.7-3.2.9.0-rhel7.6-x86_64.tgz
tar zxvf mlnx-*.tgz
cd mlnx-*/
sudo -s
./install

운영체제/버전에 맞는 것으로 설치; 
(구) http://www.mellanox.com/page/products_dyn?product_family=260&mtag=connectx_5_en_card
(신) https://network.nvidia.com/products/ethernet-drivers/linux/mlnx_en/


sudo yum install rpm-build
wget https://www.mellanox.com/downloads/MFT/mft-4.14.0-105-x86_64-rpm.tgz
tar zxvf mft*.tgz
cd mft*
sudo -s
./install.sh

(구) http://www.mellanox.com/page/management_tools
(신) https://network.nvidia.com/products/adapter-software/firmware-tools/


# mst start

# ls /dev/mst/
mt4119_pciconf0


dev 밑에 있는 mst 기기의 이름은 환경에 따라 바뀔 수 있음

# 싱글 포트인 경우
# sudo mlxconfig -d /dev/mst/mt4119_pciconf0 set LINK_TYPE_P1=2

# 듀얼 포트인 경우
# sudo mlxconfig -d /dev/mst/mt4119_pciconf0 set LINK_TYPE_P1=2 LINK_TYPE_P2=2

Device #1:
----------

Device type:    ConnectX5       
Name:           MCX556A-ECA_Ax  
Description:    ConnectX-5 VPI adapter card; EDR IB (100Gb/s) and 100GbE; dual-port QSFP28; PCIe3.0 x16; tall bracket; ROHS R6
Device:         /dev/mst/mt4119_pciconf0

Configurations:                              Next Boot       New
         LINK_TYPE_P1                        IB(1)           ETH(2)          
         LINK_TYPE_P2                        IB(1)           ETH(2)          

 Apply new Configuration? (y/n) [n] : y
Applying... Done!
-I- Please reboot machine to load new configurations.

https://community.mellanox.com/s/article/getting-started-with-connectx-5-100gb-s-adapters-for-linux


# lspci | grep -i mel
82:00.0 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]
82:00.1 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]

# ifconfig ...
# ethtool ...