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Email sending process E-mail is a kind of information transmission behavior that uses the network to transmit information to remote servers. We usually use "account @ host name" for e-mail. However, due to "malicious mail" and "spam flooding", we are not allowed to directly use the host's ip address to send mail. ...

1. Overview Performance analysis of IO has always been one of the focuses of performance analysis, and the idea of analysis is: With clear logic in the code, you can completely know which files are read and written frequently. But for performance analysts, it's often a system that's not written by them, or sometimes produced by multiple ...

k8s container resource limit Memory limit example If the container exceeds its memory limit, it is terminated. If it is restartable, kubelet will restart it like all other types of runtime failures. If a container exceeds its memory request, its Pod may be evicted when the node is out of memory. vim memory.yaml apiVersion: v1 kind: Pod ...

1. Introduction As you can see from previous blogs, the SPI Universal Interface Layer is a middle layer, which provides a series of standard interface API s and standard data structures for protocol and controller drivers. So the SPI Universal Interface Layer is a core layer of the SPI bus. The SPI Common Interface Layer code is focused on: / ...

1. iptables basic management 1.1 problems This case requires you to practice the use of iptables command and complete the following tasks as required: Close firewalld and start iptables serviceView firewall rulesAppend and insert firewall rulesDelete and clear firewall rules 1.2 scheme iptables firewall has 4 tables and 5 chains, 4 t ...

Introduction to Docker I Docker introduction www.docker.com 1.1 INTRODUCTION 1. Docker Docker Is an open source application container engine based on Go Language and compliance Apache2.0 Open source agreement. Docker Developers can package their applications and dependency packages into a lightweight and portable container, and then ...

catalogue I. elasticsearch7 6.1 installation steps II. Install kibana client (all three machines should be installed. Ordinary users should perform the following operations) III. install IK word splitter (ordinary user operation) 4. Install elasticsearch head plug-in (all three machines need to be operated. Ordinary users need ccb operation ...

Introduction and use of Jason Json is a lightweight data exchange format (also known as data serialization). Json uses a text format completely independent of the programming language to store and represent data. The concise and clear hierarchy makes Json an ideal data exchange language. It is easy for people to read and write, easy for machin ...

summary tcpdump is a packet capture tool for intercepting network packets and outputting packet contents, similar to wireshark in window. It is the preferred tool for network analysis and troubleshooting under Linux system Ordinary users cannot execute. Only users with root permission can execute We can use tcpdump to grab packets principle C ...

Communication between different hosts: ❤️ The concept of process communication originated from single machine system. Since each process runs within its own address range, the operating system provides corresponding facilities for process communication to ensure that two processes communicating with each other do not interfere with each o ...