Syncing Date and Timezone – Install and configure ntpd

For various cluster or distributed application setups it’s an explicit requirement to have date and timezone (TZ) on each node synced. The difference in date or TZ may result in serious issues, for example in case of Puppet Master/Agent setup it’s a must requirement to have the data and TZ synced across all the nodes, if not, Puppet master server being the certificate authority may issue agent certificate from the distant past or future, which other nodes will treat as expire.
For syncing data and timezone across all the nodes, for whatever reason the tool at hand is ntpd.
The Network Time Protocol daemon (ntpd) is an operating system program that maintains the system time in synchronization with time servers using the Network Time Protocol (NTP).

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Install VirtualBox 5.1 for CentOS 7/RHEL 7

VirtualBox (aka Oracle VM VirtualBox) is an open-source “full virtualization” solution by Oracle Corporation. Basically it is a hypervisor, which makes it possible to install an unmodified OS on top of your existing host OS – these environments are generally termed as virtual machines or guest machines (the base machine the Host). Hypervisors i.e. VirtualBox provide a virtualization layer i.e. making it possible for the guest machines to access the abstracted hardware resources.

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pyenv – managing multiple Python versions

You may be a mid-level Python programmer using Python 2.7.5 for sometime, but also curious about Python 3.x.x, or check for yourself what is this all the Python 2 vs 3 debate over Internet, or simply the new functionalities or conventions being introduced in Python 3.x.x. or, just a Python newbie starting off and all so confused given the Python version debate. Don’t worry, my friends you have been rescued – you can keep multiple versions of Python (as many as you like).
There may be lot ways to install multiple Python versions, in the post I’ll be focusing on doing it using penv. – as it’s the most elegant way to do so.

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