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As you know security is one of the key points during database administration. In MongoDB sharded clusters security between components of the cluster is provided …
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Selcen Sahin
New Audit Mechanism on Oracle 12c : Unified Auditing
Hello everyone, Today I want to talk about new auditing features on Oracle 12c. As you know in Oracle 11g and below versions there …
Read More »MongoDB Resync stale replica member
In a replica set if one of the members is in RECOVERING state and in the log file of that member if you see: [crayon-66a4aaf13eeca527304879/] …
Read More »MongoDb query performance
Hi guys, Today I want to talk about performance issues on MongoDB. As a dba you may informed by users or developers that the …
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How to purge sysaux tablespace
Sysaux tablespace is an auxiliary tablespace to the SYSTEM tablespace. If SYSAUX tablespace becomes unusable database functionality will remain operational. Occupants of the SYSAUX tablespace …
Read More »Unshard a sharded collection in MongoDB
Yesterday in one of our mongodb databases developer asked for unshard a sharded collection. Yes it is possible to unshard a sharded collection but …
Read More »Restore a Sharded Cluster with Database Dumps in MongoDB
Before restoring database dumps to new servers we need to install MongoDB on each system. Step 1: Installation: [crayon-66a4aaf140874420005014/] inside it: [crayon-66a4aaf140880432121979/] [crayon-66a4aaf140882034809093/] …
Read More »Automatizing backup process on sharded clusters
In sharded replicas before backup process you need to disable balancer and when backup finishes you need to enable the balancer. This process doesn’t …
Read More »Back Up a Sharded Cluster with File System Snapshots
In MongoDB we can take backups with database dumps or filesystem snapshots. In large databases it is recommended to use file system snapshots rather …
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