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15 votes

Turn off strict checking of ssh keys

The problem is that ssh presumes a 1-to-1 mapping between IP addresses and hosts. We need to break that mapping only for the IP addresses of your cloud servers. The Solution Add the following stanza ...
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  • 251
10 votes
Accepted

Does OpenStack make sense for a home server?

No, openstack is way too much of an overkill for your needs. For one, you will have to waste a decent amount of VMs just setting up for openstack elements. You also seem to have some of your ...
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9 votes

libvirt network error - no 'default' network device found

This is actually expected behaviour it seems .. something to do with how NAT forwarding is set-up by default. The system expects a 'default' network, bound to virbr0. So, if you delete that network, ...
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6 votes
Accepted

OpenStack: Can I convert a volume into an image?

In Icehouse and later you can convert Cinder volume to Glance image with upload-to-image command: cinder upload-to-image <volume> <image-name>
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6 votes
Accepted

OpenStack soft reboot instance vs. sudo reboot

OpenStack Dashboard Server Reboot Use this function to perform either a soft or hard reboot of a server. With a soft reboot, the operating system is signaled to restart, which allows for a graceful ...
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  • 176
5 votes
Accepted

Is it useful to deploy OpenStack to a single node?

OpenStack will run fine on a single machine, and this is indeed a useful setup in scenarios like evaluation or developing OpenStack itself. A tool called PackStack, which is available on RHEL variants,...
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5 votes

Apache Mesos Vs. Apache CloudStack

A comprehensive article has been recently posted covering your question. Some highlights from the article: "You can actually run Mesos on any cloud that is provisioned using OpenStack, and that’...
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5 votes

Joining variables in an openstack heat template

I found a solution using str_replace. My code looks something like: heat_template_version: 2013-05-23 description: Create network with parameters: client_code: type: string description: 4 ...
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5 votes
Accepted

Joining variables in an openstack heat template

I found a solution using 'list_join': heat_template_version: 2013-05-23 int_network: type: OS::Neutron::Net properties: name: list_join: ['-', [ {get_param: tenant}, 'net']]
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5 votes
Accepted

Should I regard openstack cloud servers as just another type of virtualization?

If you want redundancy you still need to plan for it. Cloud providers (regardless of the platform) still have outages on both the host and datacenter levels. Usually there is a pool of hosts and you ...
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  • 17.1k
5 votes
Accepted

Openstack: What the difference between nova migrate and nova evacuate?

The nova help is a bit confusing, as it frequently uses the word "server" where "instance" is actually meant, and "host" where "compute node" is meant. OpenStack's terminology has changed over its ...
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4 votes
Accepted

Openstack: Is it possible to migrate an instance from a dead compute server to a live one?

It is old question, but yes you can with nova evacuate command. Example to move vm_name to nova_compute1 node: nova evacuate vm_name nova_compute1 nova reboot --hard vm_name Instance will be ...
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4 votes

Extremely slow qemu storage performance with qcow2 images

Qcow2 file backend can be significantly slow with cache=none setting. Moreover, "-o prellocation=metadata" preallocate metadata only, and actual file data will be fragmented. In other words, the qcow2 ...
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  • 43.2k
4 votes
Accepted

What is reasonable storage failover time that most OS (VM) can tolerate?

The disk driver typically will wait until a configurable timeout is exceeded before even reporting an error for the operation requested. As you have found out, this is /sys/block/<devicename>/...
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  • 40.2k
4 votes
Accepted

How to attach an interface to an instance with the openstack client?

I also wanted to do this and eventually found openstack server add port $SERVERNAME $PORTUUID works with latest python-openstack. See here for documentation. But I really just wanted to do this ...
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  • 608
4 votes

How to make a linux VM working as a router

You are on the right track with your firewall rules. I do things the "old fashioned" way - write a script, put it in /etc and call it from /etc/rc.local. However you like to do it, here's what works ...
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  • 1,438
4 votes

How to get list of openstack Instances with Project name

The command to list all instances of a project is: openstack server list --all-projects --project $projectname The parameter --all-projects is needed to list instances that don't belong to the ...
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3 votes

KVM Dynamic Rate Limiting

As you are using Openstack, when you create a flavour you can specify the rxtx_factor. My understanding is that this is used to calculate a percentage of the rtx_cap on the network that is available ...
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  • 143
3 votes
Accepted

Deleting port on one openvswitch bridge causes change in MAC address on another bridge

It looks like it is not possible to set a persistent MAC address on an OVS bridge using the ip set link command. Instead, you need to set via ovs-vsctl: ovs-vsctl set bridge br-ex other-config:...
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  • 40.3k
3 votes
Accepted

How to remove / add public network to a server in Rackspace API

Presently only the primary account user can delete virtual interfaces from a server. This is a known bug, since all admins should be able to delete VIFs, and it has been logged with the Dev team.
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  • 146
3 votes
Accepted

Invalid parameter config_hash: Attempting to install mysql (and Openstack) via Puppet

What version of the mysql module do you have installed? (check its Modulefile) Looks like the openstack modules depend on behavior of older versions of the mysql module, and declare that correctly ...
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3 votes

Relationship between Vagrant, Docker, Chef and OpenStack (or similar products)?

I think coming from a developer background will make becoming a 'devops' actually more tricky, your question is almost 3 years old so It would be interesting to hear how you are finding the journey, I ...
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  • 1,864
3 votes
Accepted

How many VMs per core/vcpu can be run in OpenStack

OpenStack does indeed allow you to overcommit CPU resources, but the amount that you can overcommit can be limited by local configuration. By default the ratio is 16:1, meaning you can run a maximum ...
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3 votes

Apache Mesos Vs. Apache CloudStack

If you ask me it's a matter of scope. If you're doing traditional IaaS, as @user222032 already mentioned, then cloudstack will be your friend. Because using virtualization you're in the "compute" ...
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  • 313
3 votes

Openstack Cloud

If I'm understanding your question correctly, the answer is no: you cannot pool resources across multiple host servers into a single VM. A VM has only one host, though any given host can have multiple ...
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  • 15.4k
3 votes

Extremely slow qemu storage performance with qcow2 images

cache=none is probably not a good idea when you're using qcow2 files. A qcow2 file makes it appear that every access to the disk is fragmented. This means you get the random access performance of the ...
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3 votes

Is it possible to monitor how OpenStack is allocating virtual infrastructure on a physical one?

If you want the resource usage per VM/tenant, you could use Ceilometer. If you want to monitor the OpenStack services and not the VMs, you probably have to create something yourself (collectd/diamond +...
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  • 1,339
3 votes

VMware ESXi 6.0 and Openstack

ESXi doesn't support the OpenStack API directly. There's VMware Integrated OpenStack (VIO)... although I don't think it's supported to use other hypervisors with this. If you want to use vSphere as a ...
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  • 1,612
3 votes
Accepted

Multiple DNS records with different networks

I'm not quite clear what you want, but multiple entries for the same resource record in a single zone such as: h1 IN A 192.168.1.4 h1 IN A 10.14.6.4 is called round-robin DNS and the effect is ...
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  • 70.6k
3 votes

OpenStack Juno Live-Migration never completes for instances with high load and size >64GB

Failing migration due to too-busy VMs has been recognized as a problem. Unfortunately, while qemu provides a solution, it is not exposed via the libvirt API, and is thus unavailable to OpenStack. ...
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