Virtualize or not virtualize

Virtualize or not virtualize

Virtualize or not virtualize

Ever since there is virtualization especially these few years, your IT team might have been bothered by this question. To virtualize a server or….? The answer is depending. Depends on? Clearly, there are more advantages to virtualize; example license of the software is cheaper, you can install more than one instances on the same server, a virtual switch, it is portable etc.

However, there are a few things to consider that virtualization might not work for you. If you need to split the instances for different departments and it has total privacy. Virtualization does not give you true isolation, there is risk your virtualized server is accessible through the underlying virtualization OS.

Disk IO is started to divide with the number of guest machines you have deployed. The greater the number of guest machines, the slower the disk IO. If you are still using hard disk storage, this is a crucial factor for the SQL database to some.

Failure risk – if your server has failed due to hardware, you might have more than one servers are failed if you virtualized. Especially to those do not have spare resources or a virtualized cluster. Not for dedicated servers, if one failed, the rest will continue to work.

If your guest machines are not paravirtualized, there is a performance overhead, For example, a true hardware ethernet will perform 2 ~4% better than a virtualized network card.

Some software makers have realized they are missing the virtualization segment and have made changes from processor count to core count license but the end of the day virtualization will save you money if you environment permit you to do do.

 

 

A Snapshot vs a Backup

A Snapshot vs a Backup

Many have not understood what is a snapshot? What are the differences? Which is better? Today, we are here to explain to you the differences, the pros and cons of the backups and the snapshots.

Snapshot is only available to a VM. Whether they are called VPS or something else. If the instance is virtualized, a snapshot is possible. Backup is installing an agent into the guest OS or the dedicated server, transfer the partition or files into a backup storage device.

Snapshot takes an image of the instance of its current state and dumped into a compressed file format like LZO. It is only possible to restore the entire VM. to restore files, you will have to extract files after you have restored the VM to another instance which is very time-consuming.

However, you can restore files from a backup. Even a bootable partition for some backup solutions. To restore a partition, you must have a temp portable partition on the memory to restore the restored bootable partition backup. This is a very slow process especially the restoration involved a huge partition.

Files restoration is the fastest and if you need to roll back the entire server, a snapshot restoration is much faster than restoring a bootable partition. However, if your backup retention is longer, you will need lesser space on your backup devices.

Most snapshot use NFS. It is cheaper to build an NFS storage than a proprietary backup solution. Nowadays, VM snapshot uses LVM-Thin to conserve disk space, it helps reduce disk space usage significantly. There is a drawback using LVM-Thin, the server must have a faster write and read space especially restoration, otherwise, it will affect the speed on other guest machines on the same server.