Host and VM ping failed

Issues related to configuring your network
Post Reply
MottetRDSF
Posts: 1
Joined: 2021/10/15 11:24:25

Host and VM ping failed

Post by MottetRDSF » 2021/10/15 11:27:59

Hi,
I have a physical server (CentOS 7.9.2009) and I created a Linux VM (CentOS 7.6) with virtmanager.
when I do a ping from physical server to VM, I have the message Destination Host Unreachable
when I do a ping from VM to physical server, I have the message Destination Host Unreachable

How to solve this issue?

thank you in advance

To complete: on host server, ifcfg-br1 file:
DEVICE="br1"
ONBOOT="yes"
TYPE="Bridge"
BOOTPROTO="none"
IPADDR="10.250.130.17"
NETMASK="255.255.254.0"
STP="on"
DELAY="0.0"

on VM, ifcfg-eth0 file:
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=none
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=eth0
UUID=35ac110f-e9eb-45cd-88b7-bd4d05410b9f
DEVICE=eth0
ONBOOT=yes
IPV6_PRIVACY=no
IPADDR=10.250.130.18
PREFIX=24
GATEWAY=10.250.130.1
DNS1=139.53.124.51
ZONE=public

User avatar
jlehtone
Posts: 4523
Joined: 2007/12/11 08:17:33
Location: Finland

Re: Host and VM ping failed

Post by jlehtone » 2021/10/16 09:03:28

First, spanning tree protocol (STP) is for detecting loops. If you create a triangle with three switches without STP, then broadcasts will storm around. A bridge for VM's should not create a loop. (One could do so, but ...) Therefore, STP should be off.

Second, you have two different subnets. The mask 255.255.254.0 is not 24 bits.

Neither really explain the problem.

Firewall could reject all packages with host-unreachable, but that is not a default.

What do you get with:

Code: Select all

[host]$ brctl show
[host]$ ip li
[host]$ ip ro
[host]$ nmcli c s

[guest]$ ip li 
[guest]$ ip ro 
[guest]$ nmcli c s

Post Reply