similar to: Creating a private network

Hi, I've been trying to migrate some of my CentOS 7 KVM hypervisors to CentOS 8, and I have encountered the following issue while trying to load my network config: virsh:     error: Failed to start network test1     error: internal error: Network is already in use by interface virbr2 journalctl:     error : networkCheckRouteCollision:123 : internal error: Network is already in use by

Hello, I have first a question (and then may be a problem), that I have difficulties to understand and eventually to investigate. On each of my guests VM, I see constantly a RX dropped number increasing , Even if the VM does nothing ! ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.100.15 netmask 255.255.255.0 broadcast 192.168.100.255

On Tue, Jun 20, 2017 at 02:26:59AM -0400, Travis S. Johnson wrote: >Hello, > >I came across an interesting problem in my home lab a few weeks ago as I'm >prepping for my RHCE exam using Michael Jang study guide. I've been at this >for days now, and I still can't wrap my head around how two or more virtual >networks in default NAT configuration are even allowed to

Hello, I came across an interesting problem in my home lab a few weeks ago as I'm prepping for my RHCE exam using Michael Jang study guide. I've been at this for days now, and I still can't wrap my head around how two or more virtual networks in default NAT configuration are even allowed to communicate with each other despite what the libvirt documentation said. Here's the

I just wrote this to assist some Red Hat folks understanding what libvirt does with iptables, and thought it is useful info for the whole libvirt community. When I have time I'll adjust this content so that it can fit into the website in relevant pages/places. Firewall / network filtering in libvirt ======================================= There are three pieces of libvirt

Hi all, I try to understand why the network bandwidth limits are not applied to my ubuntu 16.04.2 VM (qemu-kvm driver) and I would need some insights. I create my VM network with virsh and when I issue a dumpxml on my network, I can see that bandwidth limits are set: virsh # net-dumpxml nat_limit <network> <name>nat_limit</name>

On 12/30/2013 11:25 AM, Andrew Martin wrote: > Is there a supported method for creating a fake network interface in a VM's > configuration file? I was using the below construct, however it is no longer > working for me in recent versions of libvirt (libvirt 1.0.2 with qemu-kvm > 1.4.0). I assume this wasn't working for you either because you previously had a network named

I found the answer to this question: 1. create an XML file with a fake configuration (including a subnet not in use elsewhere): <network> <name>fake</name> <bridge name='virbr1' stp='on' delay='0' /> <ip address='192.168.0.1' netmask='255.255.0.0'></ip> </network> 2. define the network: virsh net-define

Hi all, I created a two node cluster that manages virtual machines with two servers connected via a cross cable on the network 10.0.0.0/24. I want that machines that runs on different servers in the network 172.16.0.0/24 can see all the others. To make this possible I've configured a vlan on each server: ... ... 5: eth1.111 at eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc

Is it possible to configure 2 virtual nics in the same ip range ? Here is what I am trying. **** This works **************** cat nw1.xml <network> <name>nw1</name> <domain name='nw1' /> <forward mode='nat' dev='eth2'/> <ip address='192.168.101.1' netmask='255.255.255.0'> <dhcp> <range

On Tue, May 20, 2014 at 01:59:42AM -0700, Srinivas_G_Gowda@dell.com wrote: > Is it possible to configure 2 virtual nics in the same ip range ? Nope, that's unsupported. We need to key various things off the IP address + mask used for the NIC, so you can't have multiple nets with the same address + mask. > Here is what I am trying. > > > **** This works ****************

Am 2017-03-07 13:01, schrieb Michal Privoznik: > On 03/07/2017 11:44 AM, Marko Weber | 8000 wrote: >> >> >> (sorry, dont know how i put my posting into an reply to an other issue >> before, >> new posting to sepearte it, big sorry) >> >> >> >> >> Hello list, >> >> i updated on a gentoo system from libvirtd 2.5 to

I have these interfaces listed. eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.8 netmask 255.255.252.0 broadcast 192.168.3.255 inet6 fe80::e2d5:5eff:fe63:abe5 prefixlen 64 scopeid 0x20<link> ether e0:d5:5e:63:ab:e5 txqueuelen 1000 (Ethernet) RX packets 42411243 bytes 4701898681 (4.3 GiB) RX errors 0 dropped 156

Hi Mike, Thanks for the info. I'd rather run monitoring such as tcpdump from the VM if possible and not the host as a simulation of a network appliance and with the intent eventually of giving others access to the VM and not the host. Here is the xml file for the private network: <!-- WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE OVERWRITTEN AND LOST. Changes to

On Thu, Jul 23, 2020 at 03:34:03PM +0100, Rui Correia wrote: > > Is net.ipv4.ip_forward set to 0 ? > > > > > I assume you're asking if this is setup on the host and not on the VM's. > I've checked the host and it is configured like this: > $ sysctl net.ipv4.ip_forward > net.ipv4.ip_forward = 1 This is good. > Should I change it to =0 ? It

On Tue, Mar 22, 2016 at 1:57 PM, Kevin Ross <sedecim at gmail.com> wrote: > Hi Mike, > > Thanks for the info. I'd rather run monitoring such as tcpdump from > the VM if possible and not the host as a simulation of a network > Then run tcpdump on the VM. Same command or commands you'd have ran on the host node. > appliance and with the intent eventually of giving

Hi Daniel, First of all, awfully sorry for replying so late. Unfortunately your reply had gone to the Spam drawer... Also, I'm answering from Gmail's webmail which IIRC only allows for 'quote original post below'. So please forgive me for not following the proper netiquette of 'quote original post above'. > Is net.ipv4.ip_forward set to 0 ? > > I assume

Hi, I've seen this before. First, the simple steps: have you started that network? (virsh start network-name) do you have installed the tools to work with bridges in your OS? can you check if the bridge exist in your OS and if the vm's interface is attached to it? In rhel you use the command brctl to do that, don't know about ubuntu... Best Regards, DR On Thu, Apr 16, 2020 at

Hello everybody, i've defined a simple network, with no dhcp. I'd like to use dnsmasq only as a dns server. $ virsh net-dumpxml basicswitch <network> <name>basicswitch</name> <uuid>60f491d2-d6c4-6b57-8a50-081cace8dedc</uuid> <forward mode='nat'/> <bridge name='virbr1' stp='on' delay='0' /> <ip

On 06/20/2017 05:27 AM, Martin Kletzander wrote: > On Tue, Jun 20, 2017 at 10:05:19AM +0200, Martin Kletzander wrote: >> On Tue, Jun 20, 2017 at 02:26:59AM -0400, Travis S. Johnson wrote: >>> Hello, >>> >>> I came across an interesting problem in my home lab a few weeks ago >>> as I'm >>> prepping for my RHCE exam using Michael Jang study