Jul 092015
 Posted by on July 9, 2015 at 6:33 pm FAQ, Java, JVM Tuning, Troubleshooting Tagged with: , ,  No Responses »

While debugging a production crash with huge Xms(24GB) and Xmx(30GB) sizes, we got a heap dump of 18GB to analyse for out of memory root cause. We were not having any big machines to run the MAT(Memory Analysis Tool) to analyse the heap dump and all the time we were getting out of memory in MAT itself in midway of analysis. While searching on google we got few good references like this but there also we found we have to put huge Xms and Xmx for MAT itself and our laptops were not well equipped to do so.

We had 8GB laptops to analyse a 18GB dump and we had to set garbage collection alogoritms to keep the MAT getting out of memory while running it in command line mode instead of GUI as it takes more memory to analyse.


Below are few steps which you need to follow to analyse the huge heap dumps with out Out of memory errors in MAT.

1.  Download the latest MAT for here

2. cd to the MAT installation folder and open the MemoryAnalyzer.ini file and update below settings.

Note: Here we are using a 8GB laptop so settings are set accordingly. If you have higher configuration or lower you have to set the Xms and Xmx accordingly.
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Jun 122015
 Posted by on June 12, 2015 at 6:01 pm DevOps, SaltStack Tagged with:  4 Responses »

I was going through few of DEVOPS tools for automation work out of personal interest and was comparing them with respect to our inhouse environments and while comparing the Puppet Vs Chef Vs Ansible Vs SaltStack I see Salt is a very good open source tool and have the capability to manage cloud environments without buying the enterprise edition and can easily manage 1000+ servers with single master itself plus its capable of handling Docker images also.

One better thing is its marginable faster than all the configuration management tools when it comes to large deployments of 1000+ slaves connected and managed by one master. It will be really helpful for curbing out lot of man hours of manual work specially in hosted environments including the inhouse environments.

As an immediate demo in this article, we will try to show how we can eliminate pain points like:

  1. Windows Security fixes (KB) patching to 100+ servers takes huge time and weekends time to login manually to each server and do the patching.
  2. Monitoring Service status and ensuring services are running fine, network status, etc. eats out time from daily work hours.
  3. Env’s configurations states are not in control and reverting back and tracking a single change is not possible. Due to which many issues gets raised by users.

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Jun 102015
 Posted by on June 10, 2015 at 1:51 pm DevOps, Rundeck Tagged with: ,  No Responses »

While evaluating release management and runbook automation Devops tools we found rundeck quite handy. It has opensource as well as pro version for use. Installing Rundeck was easy but integrating rundeck Active Directory was not that straight forward. After trying few things we were able to integrate the Rundeck with our AD(active directory) software and could allow the users to login to rundeck GUI console using there domain credentials. All that said we still had one huddle here, i.e by default rundeck expects the authorization also from LDAP active directory in the form of groups and roles. This addition of roles and groups was not allowed in our corporate AD due to security restrictions so we had to find a way to authenticate users using rundeck active directory but authorization shall be managed locally as it’s much easier to change roles and update responsibilities and groups etc.
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Jun 102015
 Posted by on June 10, 2015 at 10:59 am DevOps, Rundeck Tagged with: ,  No Responses »

While using Rundeck I came across a very thin documentation with examples to show how to define the access control to individual roles and projects and in our company it was very much required to make different roles so that there will be segregation between who is who in rundeck system. For example we had some users which required readonly privileges to know if the job is completed and few users with run a job privilege but no modification to job  and few users needed to have privileges to modify the jobs and work flows. So in this article we will discuss on what needs to be done to have the access rights set for individual users for better control on your rundeck system.

Before going deep on configurations below is the excerpt from rundeck official url about the access control policy and mechanism.
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Jun 092015
 Posted by on June 9, 2015 at 8:57 am Automation, Installation, Must Know, Tutorials Tagged with:  No Responses »
Must Know

For one of our projects we had requirement of accessing windows machines from linux environments to run few scripts for deployment. After little search we settled for openssh server for ssh connections and cygwin for script run in windows with public key authentication to have passwordless authentication. Below are the steps needs to be followed to achieve the same.

1. Download latest OpenSSH for your windows server from Windows SSH server Download
2. We have used currently latest setupssh-6.8p1-1 version for this tutorial.
3. Double click on the setupssh-6.8p1-1.exe file and click on next button.
Windows OpenSSH server Installation
4. Click on Next button and accept the license agreements.
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