No network on Centos 7 Cloud converted from QCOW to VMDK

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carlosedp
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No network on Centos 7 Cloud converted from QCOW to VMDK

Postby carlosedp » 2017/03/17 21:07:02

I have a brand new Mirantis Openstack 9.2 deployment and I'm trying to launch some CentOS 7 images with no success.

I downloaded CentOS-7-x86_64-GenericCloud.qcow2 and converted to VMDK since my Openstack deployment is over a VMware cluster. After this, I load the image into Glance and deployed it but when the instance is launched I get no network.

I manage to log into the CentOS terminal and got that there is no interface eth0 (not present). Also there is a "eno16777728" interface in "ip a" without IP of respective confir files in network-scripts.

Both CentOS 7 1511 and 1611 have the same problem.

I tried with Cirros, Ubuntu, Debian and CentOS 6 Generic Cloud and they all work perfectly. All of them were converted and loaded into Glance with the same commands and parameters.

Thanks

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TrevorH
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Re: No network on Centos 7 Cloud converted from QCOW to VMDK

Postby TrevorH » 2017/03/17 21:26:24

If you want the old style network interface naming back then you need to read the FAQ and pass biosdevname=0 net.ifnames=0 on the kernel command line to force that. Otherwise you get the new naming convention which makes it up as it goes along - and also has a bug on vmware VMs that gives you even more ridiculous names than usual.
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carlosedp
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Joined: 2017/03/17 21:03:58

Re: No network on Centos 7 Cloud converted from QCOW to VMDK

Postby carlosedp » 2017/03/20 16:45:07

Thank you Trevor, adding the parameters to the kernel fixed the problem.

Any idea if this is a problem related to Openstack or VMware virtualization?

Thanks!

aks
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Re: No network on Centos 7 Cloud converted from QCOW to VMDK

Postby aks » 2017/03/20 17:17:06

No, it's down to the change of using "predictable" network names in C7 and above.
For maximum compatibility (and legacy support) I guess cloud/VM gop for the "non-predictable" option.

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TrevorH
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Re: No network on Centos 7 Cloud converted from QCOW to VMDK

Postby TrevorH » 2017/03/20 17:23:16

'Predictable' meaning you never know what it's going to call them until you boot it!
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aks
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Re: No network on Centos 7 Cloud converted from QCOW to VMDK

Postby aks » 2017/03/20 17:34:41

Agreed. At work on various virtualized C6.x (well possibly around 6.3 originally) I have multiple interfaces and at boot have to work out which interface is actually connected where (as the ethx names do not map to the exact same hardware every time).
Yes it is good and yes it is bad.

carlosedp
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Joined: 2017/03/17 21:03:58

Re: No network on Centos 7 Cloud converted from QCOW to VMDK

Postby carlosedp » 2017/03/21 02:22:12

Actually I fixed it for my own use by editing he qcow2 image and converting it to vmdk but I don't know what is the permanent fix to allow entone use the available qcow2 images.

Any tips on what can be done?