Author Archives: Divyashree - The GNULINUX Guy

About Divyashree - The GNULINUX Guy

I am a Linux and Opensource enthusiast. I started working on Linux early in 2007 while I was doing my Masters in Computer Science and passed out in 2010. Currently working as a DevOps Developer in in Public/Private cloud domain. my @github : https://github.com/kumarprd my @nagiosexchange : https://exchange.nagios.org/directory/Owner/divyaimca/1 my @linkedin : https://www.linkedin.com/in/priyadarshee-kumar-☁-a9415615

ORA-12519: TNS:no appropriate service handler found

The number of database processes that can run in Oracle DB is set to 150 as default which can be viewed from v$resource_limit. select * from v$resource_limit where resource_name = ‘processes’; RESOURCE_NAME CURRENT_UTILIZATION MAX_UTILIZATION INITIAL_ALLOCATION LIMIT_VALUE ————- ——————- ————— —————— … Continue reading

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pexpect alternative in python for remote connection

We generally use python pexpect module to connect system remotely with ssh and execute our tasks. But sometimes pexpect module is not found to be installed in remote systems which create problems. And this problem can be solved with the … Continue reading

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Accessing Host from Docker Container

Sometime we need to access the services that are running in the host machine to be accessible from the docker container.  e.g. In on of my project, we needed to connect to the oracle db (port 1521) from inside the … Continue reading

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SNMP Poller tool to monitor any thing on network

Few years ago, I had created one SNMP Poller tool using perl and snmp utilites that can poll OID informations from any network devices, which is kind of passive monitoring mechanism. Thought to make it Opensource under GNU GPL. The … Continue reading

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My MongoDB cheatsheet

Few years ago, I was working on one mongoDB project.Its a NoSQL database , easy to learn and its pure JSON based. I learned it myself and had created a cheatsheet for it, so I can easily recall it anytime … Continue reading

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chef attribute : avoiding “undefined method `[]’ for nil:NilClass” error

In chef, when a nested attribute that might not exist/or not crated yet, you can use rescue as a modifier to an if statement. For example, assuming that only some of your nodes have node[‘install_wls’][‘isManaged’]defined: if node[‘install_wls’][‘isManaged’] do the stuff … Continue reading

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chef knife tricks: Add a node in an environment

  Sometime during automation of a large deployment process, we have to bootstrap a node , create environment and add the node in that particular environment on the fly.   Bootstraping : 2. Create environment dynamically from inside the programme:(python … Continue reading

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