In daily life, we may need to create a socks server to provide network for other hosts. I summarized the method of creating socks service through dante-server under Ubuntu 20.04.
install dante-server
1
sudo apt install dante-server
add user for dante-server
Use this method to create a user to prevent it from logging in.
To create a private Ubuntu image, the commonly used tools are debmirror and apt-mirror. As of today (2021-05-17), these two tools have their own advantages and disadvantages.
debmirror
debmirror document debmirror has many downloading methods, and it will compare the local file with the file on the server before downloading so that only the missing files are downloaded. However, it does not seem to support multi-threaded downloading. Debmirror is downloaded one by one, so the download speed is relatively slow.
apt-mirror
apt-mirror document apt-mirror supports 20 threads to download at the same time by default. If you choose a suitable mirror station, the download speed can reach the maximum of my network. However, it does not seem to make a comparison. Although it can speed up the download start speed, sometimes some files may be lost, resulting in an incomplete mirror, so the client cannot be updated.
how to write the config file
In order to download the complete package, we need to modify the configuration file in /etc/apt/mirror.list. Use this format to ensure that the i386 package will be downloaded.
1 2
deb-amd64 http://mirrors.aliyun.com/ubuntu focal main restricted universe multiverse deb-i386 http://mirrors.aliyun.com/ubuntu focal main restricted universe multiverse
Combine them together
Therefore, in order to achieve a balance between efficiency and completeness, we can combine apt-mirror and debmirror. We can first use apt-mirror to download quickly, then we can use debmirror to check and download the missing packages. Maybe this is the best way to download the Ubuntu mirror.
Refers to a disk partition, or a device (such as RAID) that has the same function as a disk partition. It is the basic storage logical block of LVM, but compared with basic physical storage media (such as partitions, disks, etc.), it contains LVM-related Management parameters.
Volume Group (VG)
Similar to a physical disk in a non-LVM system, it is composed of one or more physical volumes PV. One or more LVs (logical volumes) can be created on the volume group.
Logical Volume (LV)
Similar to disk partitions in non-LVM systems, logical volumes are built on the volume group VG. A file system (such as /home or /usr, etc.) can be established on the logical volume LV.
When using golang to write complex projects, it is often useful to use multi-coroutine concurrency scenarios. At this time, it is easy to cause the problem of coroutine leaks due to negligence, and then produce similar memory leaks. This article focuses on the investigation of coroutine leaks, and provides ideas and practices for visual analysis of golang program memory.
Introduction to pprof
pprof is a tool for visualization and analysis of profiling data. pprof reads a collection of profiling samples in profile.proto format and generates reports to visualize and help analyze the data. It can generate both text and graphical reports (through the use of the dot visualization package).
How to use pprof
Add monitoring code
First, we need to add monitoring code in the golang program, and expose it through the http interface.
When you install the Ubuntu system on a physical machine, don’t forget to do these things to improve your computer’s performance. My experiments found that the improvement was very noticeable, based on Ubuntu 20.10.
use s-tui to monitor and test your max CPU frequency