on August 30, 2016 ·
Control groups (a.k.a. cgroups) allow you to allocate resources — such as CPU time, system memory, network bandwidth, or combinations of these resources — among user-defined groups of tasks (processes) running on a system.
You can monitor the cgroups you configure, deny cgroups access [...]
on August 22, 2016 ·
Hyper does one thing: Provide isolated environments (virtual machines) on which portable environments (containers) can be easily scheduled. Hyper uses both shared and dedicated kernels environments, believing it is the right approach to deploy multi-tenant platforms.
on August 16, 2016 ·
The latest Go release, version 1.7, arrives six months after 1.6. Most of its changes are in the implementation of the toolchain, runtime, and libraries. As always, the release maintains the Go 1 promise of compatibility, which expects almost all Go programs to continue to compile and run as before.
on August 13, 2016 ·
When I tried to setup an PPTP/L2TP VPN on one of my CentOS-7 boxes, I googled this script, it works well on my side. Highly recommended if you wanna build your own L2TP VPN server.
on August 10, 2016 ·
Shadowsocks is a fast tunnel proxy that helps bypass firewall limitations. For more details, you can refer to its homepage.
The installation of shadowsocks on CentOS-7 is pretty easy as we just need to run pip, as below:
# pip install shadowsocks
on August 2, 2016 ·
Sometimes I need to kill an established TCP session especially the long time running TCP connections that doing barely nothing, without killing the process that opens it.
on April 18, 2016 ·
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?
on March 31, 2016 ·
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 [...]
on March 14, 2016 ·
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.
on March 10, 2016 ·
How can we check whether a hard drive is SSD or HDD? There are two ways for you to find it out.
Way 1: On the latest kernels, the SSD disks are automatically detected. You can find the result typically like this:
Replace sda with your hard drive path.
$ cat /sys/block/sda/queue/rotational
You will [...]