Master Internet’s Set Up
Master Internet is one of the largest managed cloud providers in the Czech Republic. Master has a DC in Prague and Brno which are 200 kilometers apart. In each location there is a separate vCenter Server managing several VMware vSphere clusters. On top of all that sits one vCloud Director instance providing a single point of management for the customers.
As a Dell preferred partner, Master Internet had been using Dell PS4000 and PS6000 (EqualLogic) storage arrays from the very beginning. When Dell introduced more powerful, Compellent based SC8000 arrays, the legacy EqualLogics (even though still working fine) were retired. The idea being that those arrays still could be used for storing backups.
EqualLogic arrays are supremely easy to administer and offer the possibility to merge several boxes into one group with single pane of glass management. They are not the fastest though and a single logical volume can never exceed 15 TB which is a pain when you need to backup thousands of virtual machines with hundreds of terabytes of used space.
Master Internet chose VMcom Backup solution for its game changing multitenancy feature which allows individual customers to manage their backups and restores themselves. And also for their simple and fair pricing which increased backup sales several times.
VMcom helped with implementation from the ground up. The EqualLogic arrays were formatted to RAID10 in order to boost performance during write operations. The group was split into 15 TB volumes (their max size) and the volumes were mounted to a single Dell server which hosts VMcom Backup Appliance.
The host server itself was equipped with several SSD drives which act as a caching layer. This arrangement boosts performance of the aging EqualLogic storage arrays massively. Local SSDs provide low latency and fast seek operations, incomparable to large-capacity rotation drives in the EqualLogics.
Data striping across several volumes was implemented into the new VMcom release. This feature joints all 15 TB volumes into a large backup storage in a RAID0 fashion with automatic load balancing.
Last but not least, recent VMcom releases support custom timeout settings for backup jobs. By using this feature, administrators can ensure a running backup job does not interfere with normal operations during peak hours.
VMcom’s write-ahead caching scheduler was also redesigned. This feature allows VMcom to predict frequently recurring blocks of data and write them to the slow drives before they are actually needed. During backup, prepared blocks simply slot into their places without the need to perform a time expensive write operation.
After implementing all those little changes, Master Internet is capable of backing up their entire environment in 4 – 7 hours which easily fits into the backup window during off-peak hours. The time differs from day to day depending on how much data has changed.
Timeouts ensure that the backup operation never exceeds 8 hours to keep the performance of production storage arrays intact. In rare cases a backup job happens to timeout, on the following day it will first start backing up those VMs it failed to complete the previous day.
The only expense Master Internet had was to buy a couple of SSD drives for the caching layer. Thanks to VMcom technology, this small investment brought new life to retired storage arrays.