Hello all,
I've got a multi-NIC machine on which I am running Centos 6.2. I am trying to have a NIC configured with an IP address but not connected to anything. The reason for this is to create a network currently only used by VM's residing on the machine, with that NIC configured to have an IP address that is a part of that network, with a view of connecting real machines to the same network in the future. How can I implement that? Currently ifup just refuses to bring that NIC up.
Thanks.
Boris.
On 05/01/12 10:38 AM, Boris Epstein wrote:
I've got a multi-NIC machine on which I am running Centos 6.2. I am trying to have a NIC configured with an IP address but not connected to anything. The reason for this is to create a network currently only used by VM's residing on the machine, with that NIC configured to have an IP address that is a part of that network, with a view of connecting real machines to the same network in the future. How can I implement that? Currently ifup just refuses to bring that NIC up.
create a bridge interface that isn't bridged to any NICs
On Tue, May 1, 2012 at 1:46 PM, John R Pierce pierce@hogranch.com wrote:
On 05/01/12 10:38 AM, Boris Epstein wrote:
I've got a multi-NIC machine on which I am running Centos 6.2. I am
trying
to have a NIC configured with an IP address but not connected to
anything.
The reason for this is to create a network currently only used by VM's residing on the machine, with that NIC configured to have an IP address that is a part of that network, with a view of connecting real machines
to
the same network in the future. How can I implement that? Currently ifup just refuses to bring that NIC up.
create a bridge interface that isn't bridged to any NICs
-- john r pierce N 37, W 122 santa cruz ca mid-left coast
John,
Thanks! But if it is not connected to any NIC's then how would I connect external devices to it in the future?
Boris.
CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
On Tue, May 1, 2012 at 1:56 PM, John R Pierce pierce@hogranch.com wrote:
On 05/01/12 10:48 AM, Boris Epstein wrote:
Thanks! But if it is not connected to any NIC's then how would I connect external devices to it in the future?
connect the bridge to a network adapter
That's precisely what I planned on doing - but I believe the network adapter needs to have an address first. Then you bridge pseudo adapters to it. It would all be fine but I can't take this initial step of assigning an IP address to the NIC in question.
Boris.
On 05/01/12 11:03 AM, Boris Epstein wrote:
That's precisely what I planned on doing - but I believe the network adapter needs to have an address first. Then you bridge pseudo adapters to it. It would all be fine but I can't take this initial step of assigning an IP address to the NIC in question.
no, no. the BRIDGE pseudodevice has the IP, network adapter(s) that are bridged to it don't have their own IP at all
On 05/01/2012 02:46 PM, John R Pierce wrote:
On 05/01/12 11:03 AM, Boris Epstein wrote:
That's precisely what I planned on doing - but I believe the network adapter needs to have an address first. Then you bridge pseudo adapters to it. It would all be fine but I can't take this initial step of assigning an IP address to the NIC in question.
no, no. the BRIDGE pseudodevice has the IP, network adapter(s) that are bridged to it don't have their own IP at all
If it helps, I show how to create a bridge as part of a bigger tutorial. I show ethX -> bond -> bridge, but you can drop the bond and go straight from ethX -> bridge.
https://alteeve.com/w/2-Node_Red_Hat_KVM_Cluster_Tutorial#Creating_Some_Netw...
On Tue, May 1, 2012 at 3:12 PM, Digimer lists@alteeve.ca wrote:
On 05/01/2012 02:46 PM, John R Pierce wrote:
On 05/01/12 11:03 AM, Boris Epstein wrote:
That's precisely what I planned on doing - but I believe the network adapter needs to have an address first. Then you bridge pseudo adapters
to
it. It would all be fine but I can't take this initial step of
assigning an
IP address to the NIC in question.
no, no. the BRIDGE pseudodevice has the IP, network adapter(s) that are bridged to it don't have their own IP at all
If it helps, I show how to create a bridge as part of a bigger tutorial. I show ethX -> bond -> bridge, but you can drop the bond and go straight from ethX -> bridge.
https://alteeve.com/w/2-Node_Red_Hat_KVM_Cluster_Tutorial#Creating_Some_Netw...
-- Digimer Papers and Projects: https://alteeve.com _______________________________________________
I found a solution that seems to work best for now. If you go into /etc/sysconfig/network-scripts/ and edit the ifcfg file corresponding to the NIC in question (in my case, ifcfg-eth1) and change the ONBOOT flag to "yes":
ONBOOT=yes
then the interface comes up with the right address regardless of whether it is physically connected to anything via an ethernet cable. I intend to bridge both virtual and physical devices to it but that will be the next step.
Thanks to everyone who helped.
Boris.
-
Boris Epstein -
Digimer -
John R Pierce