When I try to build a OpenShift Origin cluster, I noticed that it’s a bit hard to have an intimate knowledge of its installation. This post focused on this topic, and describes how to use openshift-ansible to install an Origin cluster on several servers.
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Scripting
ZooInspector: zookeeper graphic interface
I just created a pre-compiled zooinspector, and tested it working well on CentOS and macOS, and should work on windows too.
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How To Install and Configure Rocket.Chat on CentOS
Rocket.Chat is one of the most feature-rich open-source Slack alternatives, featuring group chat, direct messaging, private rooms, desktop notifications, media embedding, link previews, file uploading, voice/video chat, screensharing, and more. There are native applications for Windows, Mac, and Linux, as well as mobile applications for iOS and Android. Developers can also use hubot to integrate […]
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Whois: command line query for spam-infected domains
When run whois in command line, we sometimes cannot get the expected whois information, but something like below, $ whois github.com Whois Server Version 2.0 Domain names in the .com and .net domains can now be registered with many different competing registrars. Go to http://www.internic.net for detailed information. GITHUB.COM.KHALEDELANSARI.COM GITHUB.COM [..]
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Extract and Compress 7z files in command line
Extract and Compress 7z files in command line 7-Zip is a file archiver with a high compression ratio. The file compressed by 7-Zip has an extension ”.7z”. Here is a list of main features of 7-Zip, which is from its official website:
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Smart ways to purge a RabbitMQ queue
In a recent benchmark, we got a very large queue in one of our online RabbitMQ cluster, which had more than 20mm messages in a single queue (occupying 5-6 gigabytes memory). Then how can we purge the large queue effectively?
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RabbitMQ: remove node from cluster
When a node is no longer meant to be part of a RabbitMQ cluster, we’d remove it explicitly from the cluster. To remove a node from a cluster, there are basically two ways, get itself remove locally, or remove it remotely from the reset nodes. Here suppose we have a cluster consist of three RabbitMQ […]
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Determine the up time of an TCP connection on Linux
As a typical use case for troubleshooting, we may need to find out the up time of an established socket connection. Well, how can we do that inside a running Linux system? I faced this issue this afternoon, and got some luck finally. Note that it’s limited to TCP and UDP.
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ZooKeeper: The Four Letter Commands
ZooKeeper responds to a small set of commands. Each command is composed of four letters. When we issue the commands to ZooKeeper via telnet or nc, we would get corresponding response.
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lsof: command usage example
Lsof is used to list open files. Lsof follows Unix philosophy closely. It does just one task and it does it perfectly — it lists information about opened files in a running system. An open file can be a regular file, a directory, a block device, a pipe file, a symbolic link, a socket stream, etc.
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