[Linux]: SSH between two EC2 hosts

May 8, 2015 · by dbversity · in Linux

Using username “ec2-user”. Authenticating with public key “imported-openssh-key” Last login: Fri May 8 12:23:16 2015 from 49.205.126.24 __| __|_ ) _| ( / Amazon Linux AMI ___|\___|___| https://aws.amazon.com/amazon-linux-ami/2015.03-release-notes/ 11 package(s) needed for security, out of 36 available Run “sudo yum…

[MariaDB]: MariaDB yum installation

May 7, 2015 · by dbversity · in MariaDB

Choose the yum repo as per your linux flavour and place as below. [root@dbversityhost yum.repos.d]# pwd /etc/yum.repos.d [root@dbversityhost yum.repos.d]# [root@dbversityhost yum.repos.d]# [root@dbversityhost yum.repos.d]# cat /proc/version Linux version 3.14.35-28.38.amzn1.x86_64 (mockbuild@gobi-build-64012) (gcc version 4.8.2 20140120 (Red Hat 4.8.2-16) (GCC) ) #1 SMP…

PostgreSQL Installation using Yum

May 7, 2015 · by dbversity · in PostgresSQL

[root@ip-10-0-0-14 ec2-user]# sudo yum install postgresql-server postgresql-* Loaded plugins: priorities, update-motd, upgrade-helper amzn-main/latest | 2.1 kB 00:00 amzn-updates/latest | 2.3 kB 00:00 4 packages excluded due to repository priority protections Resolving Dependencies –> Running transaction check —> Package postgresql-jdbc.noarch 0:8.4.701-8.11.amzn1…

[PostgreSQL]: Data directory is not empty! Error

May 7, 2015 · by dbversity · in PostgresSQL

[root@ip-10-0-0-228 ec2-user]# service postgresql initdb Data directory is not empty! [FAILED] [root@ip-10-0-0-228 ec2-user]# Clean-up the data files & restart [root@ip-10-0-0-228 ec2-user]# ll -lhtr /var/lib/pgsql9/data/ total 88K -rw——- 1 postgres postgres 4 May 5 09:32 PG_VERSION drwx—— 2 postgres postgres 4.0K…

[MongoDB]: Index Data

April 27, 2015 · by dbversity · in MongoDB

Question : – ============================================ I’ve a quick question on Covered/IndexOnly Index – it’s saying query goes to index collection – not to actual collection; but I don’t see any entries in system.indexes collections except 2 – I’m little confused here….

How do I change DB Query shellBatchSize in MongoDB

April 25, 2015 · by dbversity · in MongoDB

By default MongoDB displays 20 records in the results for any DB query (which results more than 20 records ) & you can see the next set of result by pressing ‘it’ (iteration) in the prompt. However, you can change the default…

[MongoDB]: Orphaned documents

April 24, 2015 · by dbversity · in MongoDB

Orphaned document In a sharded cluster, orphaned documents are those documents on a shard that also exist in chunks on other shards as a result of failed migrations or incomplete migration cleanup due to abnormal shutdown. Delete orphaned documents using…

[AuroraDB]: How to determine to which DB Instance we connected to

April 23, 2015 · by dbversity · in AuroraDB

Determining Which DB Instance You Are Connected To You can determine which DB instance in an Aurora DB cluster that a connection is connected to by checking the innodb_read_only global variable, as shown in the following example. SHOW GLOBAL VARIABLES…

[AuroraDB]: How to monitor replica lag