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Not Enough Hosts Available error

asked 2015-10-07 05:43:20 -0600

matansab gravatar image

Hi, I Installed RDO allinone on a CentOS7 VM, everything seems to be ok except one thing. I have 2 images: one is cirros (12.6 MB) and the other is Fedora22(218MB).

I can create an instance of cirros but can't create an instace of Fedora and I get:

Error: Failed to perform requested operation on instance "Fedora1", the instance has an error status: Please try again later [Error: No valid host was found. There are not enough hosts available.].

I edited the nova.conf file and changed ram_allocation_ratio=1.5 to ram_allocation_ratio=3 but still didn't help.

Any idea ? What logs should I look at that might help me (and you..) to fix this problem?


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Which flavor you selected for F22, how much free space on hard drive, RAM ?

dbaxps gravatar imagedbaxps ( 2015-10-07 06:00:10 -0600 )edit

I chose m1.small (Root Disk - 20 GB and RAM - 2,048 MB). In project limits I see "Total RAM 0 of 51,200MB Used" is that what you mean or the VM's free space of RAM and Hard Drive?

matansab gravatar imagematansab ( 2015-10-07 06:29:07 -0600 )edit

look for the available resources on the compute node ,whether there is enough disk and RAM free,you may want to check for the logs too

sahil gravatar imagesahil ( 2015-10-07 06:31:48 -0600 )edit

free -m : total used free shared buff/cache available Mem: 2848 2336 336 7 175 335 Swap: 1639 1538 101

matansab gravatar imagematansab ( 2015-10-07 06:32:37 -0600 )edit

run df -h for the storage too..

sahil gravatar imagesahil ( 2015-10-07 06:37:04 -0600 )edit

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answered 2015-10-07 06:53:45 -0600

sahil gravatar image

The issue is related to the storage ,you may want to get more resources on your compute node so as to spawn the VM with the required size !

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but where you can see that I don't have enough storage?

matansab gravatar imagematansab ( 2015-10-07 07:36:06 -0600 )edit

answered 2015-10-10 17:57:27 -0600

germs gravatar image

Are you able to build at all? If you source your credential file then run "nova service-list" what is the status of your compute node? if you copy and paste the output we may be able to help more.. without knowing more, it is hard to say how precisely to fix... but in case it is resources...

[resource limitation]

Look at the logs for nova-conductor, nova-scheduler, and nova-compute. You could do something like;

grep -Rni <instance-uuid failing="" to="" build=""> /var/log/nova/*

It should tell you which resource you are lacking... (disk, vcpu, ram) so you can adjust accordingly. You could probably create a new flavor using a smaller pool of base resources and get your instance created. (

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Asked: 2015-10-07 05:43:20 -0600

Seen: 3,404 times

Last updated: Oct 07 '15