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I have a Centos 7 installed on vSphere with two Nic (eth0 and eth1) eth0 - 10.10.1.1 eth2 - 192.168.1.1

both IP assigned by DHCP. When reboot server first time - eth0 (10.10.1.1) is responding for pings and eth1 not. When reboot second time - eth0 not responding to ping, but eth1 does. Third reboot - eth0 respond; eth1 not and this happens everytime when I reboot a server.

I have checked eth0 and eth1 after each reboot - all IP stay the same for each interface.

Any help or ideas to where should i dig in to is appreciated.

@SmallLoanOf1M thanks for the hints: here are a results: after few reboots: "ip a" and "ip link" all the same, but "ip route" is different everytime I reboot:

1 st reboot:# ip link
   default via 10.10.1.2 dev eth0 proto static metric 100
   default via 192.168.1.2 dev eth1 proto static metric 101
   10.40.1.3 via 10.10.1.2 dev eth0 proto dhcp metric 100
   10.10.1.0/24  dev eth0 proto kernel scope link src 10.10.1.1 metric 100
   192.168.1.0/24 dev eth1 proto kernel scope link src 192.168.1.1 metric 100

2 reboot: ip link

  default via 192.168.1.2 dev eth1 proto static metric 100
   default via 10.10.1.2 dev eth0 proto static metric 101
   10.40.1.3 via 192.168.1.2 dev eth1 proto dhcp metric 100
   10.10.1.0/24 dev eth0 proto kernel scope link src 10.10.1.1 metric 100
   192.168.1.0/24 dev eth1 proto kernel scope link src 192.168.1.1 metric 100
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    More details are needed here. Post your network configurations on both the hypervisor and the guest. When you can't contact an interface, log into the console of that guest and review the output of ip a, ip link, and ip route. If you don't see the problem, post that output here as well. – Spooler Oct 5 '17 at 17:59
  • You might have a VLAN issue on your physical uplink NICs. I would check that the VLAN(s) your using are correctly configured on all your physical NICs. Is the VM changing hosts when it reboots? If so you will need to check all physical nic's in your cluster. If your using NIC teaming on the host you can also check your load balancing policy at your virtual switch. – SpiderIce Oct 5 '17 at 19:09
  • @SpiderIce Yes we are using NIC teaming and no, it is not changing host when it reboots... Will check VLAN and balancing policy as well... – Telepuzik Oct 5 '17 at 19:13
  • @Telepuzik a quick test could be to VMotion your VM to other hosts in the cluster to see if the issue follows the VM or if its just on that host. – SpiderIce Oct 5 '17 at 19:23
  • @SpiderIce we have 5 hosts and same issue appears on all of them... I will try to create brand new image from new image to see if it will behaving same – Telepuzik Oct 5 '17 at 19:44

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