I'm working on a projet on OpenStack. I have installed OpenStack by creating two virtual machines, one for the controller node and the other for the compute node.
Actually, I want to test an example of live migration on openstack and I have found a video which describes the aproch. As the video shows, I need to have 2 compute nodes, and I want to know if I just need to create a second compute node or this second compute should be created at the phase of installation of openstack.
This is the link of the video that I have watched: https://www.youtube.com/watch?v=_4vJUYFGbEM
Thank you
It doesn't matter when you add the compute nodes (During the install or later on). Please also remember that the live-migration piggy backs on the hypervisor. So depending on hypervisor that one uses, this may or may not be possible.
Please look at this http://docs.openstack.org/admin-guide/compute-configuring-migrations.html#section-configuring-compute-migrations to ensure that the migration capability exists
It simply boils down to a few things
The storage is not moved in case of a live migration, so if you have a VM with instance storage, you will need to have a shared file system like NFS or something, If you have an instance backed by a cinder volume you will be able do the migration without the shared storage.
The Nova-Compute application needs to be installed on the destiantion
The hypervisor version should be the same.
I hope this clarifies.
Either works. OpenStack allows you dynamically add and remove computes nodes from a cloud environment.
Please refer to http://docs.openstack.org/admin-guide/compute-configuring-migrations.html for extra details.
Live migration for light instances can be done over network ,without shared storage, but for heavy instances ,shared storage or shared volume will be preferred. As you mentioned you have two compute nodes ,theirs nova storage should be shared storage.
Long answer short in my perspective,
You can add/remove compute node at any time from an OpenStack installation.
For adding compute, follow installation guide to add new compute node right from environment setup.
Also, dont forget to install networking part in your new Compute node.
Related
I want to check whether there are sufficient resources available to create an instance of specific flavor without creating the instance. I tried stack --dry-run but it does not check whether there are available resources.
I also tried to go through CLI and rest api docs, but did not find any other solution than
to check available resources on each hypervisor and calculate it manually (compare it with resources required by the flavor). Isn't there any easier solution, like CLI command that would give me a yes/no answer?
Thank you.
Working on creating an OpenStack environment under Fuel for 18 XenServer based physical servers based on some prior development work which started with 4 physical servers. In the original configuration, there was only one OpenStack controller. Due to the XenServer hypervisor requirement, the images have to be custom massaged. This induced the developers to use the OpenStack CLI client and the glance image-create command for image installation, vs. using the Fuel Horizon dashboard GUI.
I'm adding at least two other controllers as recommended by best practices.
The question is pretty generic, I hope.
When using the OpenStack client CLI glance command, you set up the environment for communication purposes. Does the glance command in this configuration create the image on ALL controllers or just one?
When I look at the available images via the Fuel Horizon dashboard, the newly created image IS available. My concern is whether it is on all of the controllers? And if not, is there a way to level set all of the controllers WRT images?
Thank you for your time,
Ed Kiefer
If you have two controllers (and one Openstack region) configured properly. You should only ever need to upload the image once. If it is only available from one controller, something with your setup is wrong.
I'm looking to implement failover (master/slave) for Karaf. Our current
server setup has two application servers that have a shared SAN disk where
our current Java applications are installed in a single location and can
be started on either machine or both machines at the same time.
I was looking to implement Karaf master/slave failover in a similar way
(one install being shared by both app servers), however I'm not sure that
this is really a well beaten path and would appreciate some advice on
whether the alternatives (mentioned below) are significantly better.
Current idea for failover:
Install Karaf once on the shared SAN and setup basic file locking on this
shared disk.
Both application servers will effectively initiate the Karaf start script,
however only one (the first) will fully start (grabbing the lock) and the
second will remain in standby until it grabs the lock (if the master falls
over)
The main benefit I can see from this is that I only have to manage
deploying components to one Karaf installation and I only need to manage
one Karaf installation.
Alternatives:
We install Karaf in two separate locations on the shared SAN and setup to
lock to the same lock file.
Each application server will have their own Karaf instance, thus start
script to run.
This will make our deployment slightly more complicated (2 Karaf
installations to manage and deploy to).
I'd be interested if anyone can indicate any specific concerns that they
have with the current idea.
Note: I understand that Karaf-cellar can simplify my Karaf instance
management, however we would need to undertake another round of PoCs etc..
to approve our company use of cellar (as a separate product). Something
that I'd like to migrate to in the future.
Take a look at the documentation
This is from the documentation on how to set a lockfile for HA:
karaf.lock=true
karaf.lock.class=org.apache.karaf.main.lock.SimpleFileLock
karaf.lock.dir=<PathToLockFileDirectory>
karaf.lock.delay=10000
as can be seen there, you can also set a level for the bundle start-levels to start or not to start:
karaf.lock.level=50
What would be the best /better way to transfer repository content from one Alfresco (enterprise edition) to another instance running on a different server. Currently we copy the entire Alfresco database & file system under alf_data but that needs a down time on the servers.
I would require a mechanism without down time & the repository data be copied from one instance to another. Is there any way this is possible ?
In addition to Heiko's solution, you might be interested in:
The out-of-the-box replication service, which wouldn't be good for replicating your entire repo, but can be used for replicating a handful of nodes from one server to another.
A solution from Parashift which allows one- and two-way replication of nodes between servers.
An Alfresco presentation on using Apache Camel and Apache Kafka to replicate nodes between servers. This is available through Alfresco's professional services organization, but it may make it into the product at some point. Or you could use it as inspiration to write your own solution.
What is your intention? A standby system, a real copy, an external private cloud with a subset of data?
If you just need a 100% clone you can script backup & restore without downtime on the source server. Downtime is limited to the db and index restore on the target system. Your script shouldn't copy life data from solr index - use the backup done by the solr backup job instead. Depending on the database you use online db backup shouldn't be an issue.
Our Alfresco Virtual Appliance has preconfigured scripts and jobs for this task to start an additional alfresco instance from snapshot backups without copying the contentstore (we call this Alfresco Time Machine).
If your aim is an external private cloud server or a road warrior solution ecm4u has a commercial alfresco module to sync very efficient a subset of modified nodes including metadata/types/aspects (list of types and aspects needs to be defined). This sync provides a REST interface for automation and also manual execution from alfresco's admin console. We support mix of alfreso versions and editions. At the moment this sync is implemented as a unidirectional sync but could be extended as a bidirectional sync.
I recently did this task of installing 2 alfresco instances on my local running on 2 different ports.
While performing some tasks, I realized that 2 instances having same Repository ID is creating issues.
I was able to change the repository ID of one of them following below steps:
update alfresco-global.properties:
db.name="Add new DB Name"
(Alfresco will create a db db.name mentioned here while initializing)
and restart the server
If you are still facing issues, try deleting solr indexes under alf-data folder.
I have created a Zone, Pod and Cluster on CloudStack.I have also added a host in the Cluster, added Primary Storage and Secondary Storage. But in System VMs, nothing is listed. Also, in the logs a message "No running ssvm is found, so command will be sent to LocalHostEndPoint" comes.
Somehow I deduced that due to this, template is not being added and consequently Instances can't be created as Instances use templates to add OS in VMs.
Can anybody please help to point out and sort the problem which may be the cause here.
You need to manually install the "system VM" templates. These are the images for worker VMs that CloudStack deploys to run system services. SSVM is an example of a SystemVM. It is responsible for copying templates to secondary storage.
See Prepare the System VM Template in the installation guide.