[root@ovirt-hv2 ~]# cat /etc/redhat-release 

CentOS Linux release 7.5.1804 (Core)

[root@ovirt-hv2 ~]# cat /etc/sysconfig/network-scripts/ifcfg-ib0

DEVICE=ib0

BOOTPROTO=static

IPADDR=172.16.0.207

NETMASK=255.255.255.0

ONBOOT=yes

ZONE=public

[root@ovirt-hv2 ~]# ifup ib0

Error: Connection activation failed: No suitable device found for this connection.

Aug 22 11:31:50 ovirt-hv2 kernel: IPv4: martian source 172.16.0.87 from 172.16.0.49, on dev ib0

Aug 22 11:31:53 ovirt-hv2 NetworkManager[1070]: <info>  [1534951913.7486] audit: op="connection-activate" uuid="2ab4abde-b8a5-6cbc-19b1-2bfb193e4e89" name="System ib0" result="fail" reason="No suitable device found for this connection.

[root@ovirt-hv2 ~]# ip a

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000

    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

    inet 127.0.0.1/8 scope host lo

       valid_lft forever preferred_lft forever

2: em1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master ovirtmgmt state UP group default qlen 1000

    link/ether 50:9a:4c:89:d3:81 brd ff:ff:ff:ff:ff:ff

3: em2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000

    link/ether 50:9a:4c:89:d3:82 brd ff:ff:ff:ff:ff:ff

4: p1p1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000

    link/ether b4:96:91:13:ea:68 brd ff:ff:ff:ff:ff:ff

5: p1p2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000

    link/ether b4:96:91:13:ea:6a brd ff:ff:ff:ff:ff:ff

6: idrac: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000

    link/ether 50:9a:4c:89:d3:84 brd ff:ff:ff:ff:ff:ff

    inet 169.254.0.2/16 brd 169.254.255.255 scope global idrac

       valid_lft forever preferred_lft forever

7: ib0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 2044 qdisc mq state UP group default qlen 256

    link/infiniband a0:00:02:08:fe:80:00:00:00:00:00:00:ec:0d:9a:03:00:1d:13:41 brd 00:ff:ff:ff:ff:12:40:1b:ff:ff:00:00:00:00:00:00:ff:ff:ff:ff

8: ovs-system: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000

    link/ether 12:b4:30:22:39:5b brd ff:ff:ff:ff:ff:ff

9: br-int: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000

    link/ether 3e:32:e6:66:98:49 brd ff:ff:ff:ff:ff:ff

25: ovirtmgmt: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000

    link/ether 50:9a:4c:89:d3:81 brd ff:ff:ff:ff:ff:ff

    inet 10.0.0.183/16 brd 10.0.255.255 scope global ovirtmgmt

       valid_lft forever preferred_lft forever

26: genev_sys_6081: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65000 qdisc noqueue master ovs-system state UNKNOWN group default qlen 1000

    link/ether aa:32:82:1b:01:d9 brd ff:ff:ff:ff:ff:ff

27: ;vdsmdummy;: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000

    link/ether 32:ff:5d:b8:c2:b4 brd ff:ff:ff:ff:ff:ff

[root@ovirt-hv2 ~]# lspci -v | grep Mellanox

01:00.0 Network controller: Mellanox Technologies MT27500 Family [ConnectX-3]

Subsystem: Mellanox Technologies Device 0051

[root@ovirt-hv2 ~]# /etc/init.d/openibd status

  HCA driver loaded

Configured IPoIB devices:

ib0

Currently active IPoIB devices:

ib0

Configured Mellanox EN devices:

Currently active Mellanox devices:

ib0

The following OFED modules are loaded:

  rdma_ucm

  rdma_cm

  ib_ipoib

  mlx4_core

  mlx4_ib

  mlx4_en

  mlx5_core

  mlx5_ib

  ib_uverbs

  ib_umad

  ib_ucm

  ib_cm

  ib_core

  mlxfw

  mlx5_fpga_tools