November 6, 2019 Vignesh Sathiyanantham

All websites available on the internet are vulnerable to hacking attempts, DDOS attack, Data loss, This could happen to WordPress websites as well. WordPress has core files, the wp-content folder where the theme, plugin and the user uploaded post media are available, Configuration files which has your database configuration etc and the database contain every post, every comment and every link you have on your blog. If any of the core files, the configuration is corrupted or lost we can rebuild it, but if your wp-content and your database get erased or corrupted, you stand to lose everything on your…

September 19, 2019 Vignesh Sathiyanantham

Backup rotation/retention scheme is the how long the backup is retained on the media, many techniques have evolved over time to balance the data retention and the restoration costs. Grandfather-father-son is a very common scheme used in the backup retention strategy. In which there are three or more backup cycles such as daily, weekly and monthly. the daily backups are rotated on daily basis using FIFO mechanism, the weekly backups are rotated on a weekly basis and the monthly on a monthly or quarterly basis. Common example The hourly backup (son) are rotated on hourly with one promoted to father…

September 18, 2019 Vignesh Sathiyanantham

Amazon EBS enables users to backup volumes ar any time using EBS snapshots, Snapshots retain the data from all completed I/O operations, allowing you to restore the volume to its exact state at the moment before backup (referred to as crash-consistency). Previously when we take the snapshots of all the disks of an EC2 instance, we need to call create snapshot API for all disks recently Amazon introduced the Create snapshot of the Instance ( creates the snapshot of all the volumes attached to the instance) This is something similar to the on-premise storage array feature of Consistency group for…

September 17, 2019 Vignesh Sathiyanantham

In today’s data center industry there is a misconception about the storage snapshot as a Backup. The main one is storage snapshots are not backup, they are just point-in-time copies. It’s unclear from where the idea came from. Backup is a collection of data stored on (usually removable) non-volatile storage media for purposes of recovery in case the original copy of data is lost or becomes inaccessible; also called a backup copy. To be useful for recovery, a backup must be made by copying the source data image when it is in a consistent state. – The SNIA ( Storage…

August 31, 2019 Vignesh Sathiyanantham

In recent posts, we have discussed adding your AWS account to Nimesa to do the data protection. In this post, we will discuss application-consistent backups of your MySQL on EC2 instance. To know to install MySQL Server on Amazon Linux 2 on AWS Cloud click here Read here more about consistent, app-consistent, crash-consistent backup Nimesa supports pre and post script hooks to perform the specific operation before or after a backup, example if your Instance is running Oracle and you want to enable hot backup mode before performing backup you can write the script and upload to pre-script There is…

August 21, 2019 Vignesh Sathiyanantham

Recovery Point Objective (RPO) and Recovery Time Objective (RTO) are two of the most important parameters of the disaster recovery (DR) or data protection planning. These are the objectives/decision points for choosing the optimal backup software. Recovery Point Objective (RPO) Recovery Point Objective (RPO) describes up to what point in time could the business-critical data can be recovered in other words the last point where the data is in a usable format If you back up all or most of your data in regularly scheduled 24-hour increments, then in the worst-case scenario you will lose 24 hours’ worth of data….

August 21, 2019 Vignesh Sathiyanantham

Who uses MongoDB? Based on the online resource* there are 37,658 Companies using MongoDB, MongoDB is most often used by companies with 10-50 employees and 1M-10M dollars in revenue, and the market share is about 5.0% and also many financial services using the MongoDB Data is always critical whether its RDBMS or NoSQL or Flat files AWS EBS Volume Snapshot is block-level incremental snapshots, which is one of the best and efficient way to protect the Data in the EC2 environment, you might have read lots of posts, whitepapers about advantages of using the snapshot technology. But the Snapshots of…

August 18, 2019 Vignesh Sathiyanantham

When I am setting up the Disaster recovery plan for the MS SQL Databases in ZFS Volume, I faced permission issue while running ZFS send/receive command from a non-root account root@vigneshzfs:/home/vignesh# sudo zfs send sql-pool/disk1@aug18 | ssh ubuntu@10.7.8.25 zfs recv aws-pool/sql-pool-aug18 ubuntu@10.7.8.25’s password: cannot receive new filesystem stream: permission denied So my sender is vignesh and the receiver is ubuntu both are a non-root account On the sender side, I used these permissions sudo zfs allow -u vignesh send,snapshot,hold sql-pool And on the receiver side sudo zfs allow -u ubuntu compression,mountpoint,create,mount,receive aws-pool After setting up this permission I can send…

May 2, 2019 Vignesh Sathiyanantham

Failure rate depends more on the number of disk blocks modified since the last snapshot of the EBS volume than the total size of the volume. EBS has a listed failure rate of 0.1% – 0.4% annually, compared to a commodity disk’s rate of 4%. At first glance, this appears to be great, but this is somewhat misleading as any real production setup will use some sort of RAID. Using a RAID 1 with two drives failing at 4% would give a failure rate of 0.16% annually, which appears to be line with EBS. As long as the failed drive…

May 2, 2019 Vignesh Sathiyanantham

Creating a full backup in the SQL server using SSMS is very simple, but if you have 10’s of databases you find bit difficult to backup all databases in one go. So i write a small Powershell script which gets the list of databases and takes the backup except the system databases https://gist.github.com/asvignesh/9c2f275c9418b038022ceffa94ba2152 Run the script with Server name and the backup directory as parameters .\BackupAllDatabases.ps1 -serverName NW\CLUST -backupDirectory c:\backupdir