Skip to main content
Advanced Search
Search Terms
Content Type

Exact Matches
Tag Searches
Date Options
Updated after
Updated before
Created after
Created before

Search Results

422 total results found

Install fnOS on MBP 2015

fnOS

Create a bootable USB from an ISO using dd command. Official Installation Document Download fnOS https://fnnas.com/download List Disk Info diskutil list outputtodo Write ISO sudo dd if=fnos-0.9.21-1062.iso of=/dev/rdisk2 bs=1m status=progress Output 228...

installation
mbp2015
fnos

binlog

MySQL Quick Start

Show Variables SHOW VARIABLES LIKE 'log_bin'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_bin | ON | +---------------+-------+ 1 row in set (0.01 sec) binlog Path /var/lib/mysql/binglog.index /var/lib/mysql...

mysql
binlog

Data Transmission Service

Aliyun

数据传输服务(Data Transmission Service,简称DTS)支持关系型数据库、NoSQL、大数据(OLAP)等数据源,集数据迁移、订阅及实时同步功能于一体,能够解决公共云、混合云场景下,远距离、秒级异步数据传输难题。其底层基础设施采用阿里双11异地多活架构,为数千下游应用提供实时数据流,已在线上稳定运行7年之久。 Cost 400 RMB / Month / Instance Single way sync Micro spec(200 RPS)

Commands

macOS

Get NIC/IP Wiredifconfig en0 Wi-Fiifconfig en1 en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500 options=50b<RXCSUM,TXCSUM,VLAN_HWTAGGING,AV,CHANNEL_IO> ether d0:11:e5:85:a5:ba inet6 fe80::89e:c9c7:13f0:a7fe%en0 ...

macos

Install Java8 on macOS

Java

Oracle 1.8 is only support x86. Azul Zulu JDK 8 brew install --cask zulu@8 java -versionopenjdk version "1.8.0_462" OpenJDK Runtime Environment (Zulu 8.88.0.19-CA-macos-aarch64) (build 1.8.0_462-b08) OpenJDK 64-Bit Server VM (Zulu 8.88.0.19-CA-macos-aarch64)...

programming-languages
java

ipmitool

Server Commands

Installation brew install ipmitool Fan Query the fan sensor status from a server’s BMC (Baseboard Management Controller) via IPMI. ipmitool -I lanplus -H 192.168.x.x -U admin -P admin sdr type Fan FAN1_RPM | 41h | ok | 29.1 | 2900 RPM FAN2_RPM | 42h | ok | ...

Navigation

Aliyun Console

Home Console https://home.console.aliyun.com/home/dashboard/ProductAndService Kubernetes (ACK) https://cs.console.aliyun.com/ Yaochi Database https://yaochi.console.aliyun.com/overview DMS https://dms.aliyun.com/ Database Gateway (DG)

Database Gateway

Aliyun Database

数据库网关(Database Gateway)是一种支持私网数据库远程访问的数据库连接服务。通过数据库网关,用户可以使用应用程序或云服务访问并管理本地IDC或其他云厂商的数据库。 首页:https://www.aliyun.com/product/dg 文档:https://help.aliyun.com/document_detail/124253.html 新建网关 安装 Agent

AMD EPYC 9124

CPU AMD

Official Introduction Specification 属性 规格 Name AMD EPYC™ 9124 Family EPYC Series EPYC 9004 Series Form Factor Servers Regional Availability Global, China, NA, EMEA, APJ, LATAM # of CPU Cores 16 # of Threads 32 Max. Boost Clock Up to 3.7 G...

amd
hardware
cpu

Architecture

Java Quick Start

JRE vs JVM ┌──────────────────────────┐ │ 物理服务器 │ │ │ │ ┌──────────────────┐ │ │ │ JRE │ │ │ │ (共享文件类库) │ │ │ │ /usr/lib/jvm/... │ │ │ └──────────────────┘ │ │ ...

java
arch
jre
jvm

Beep Code

Server Troubleshooting

服务器发出蜂鸣声(beep/buzzer)通常是在 硬件或系统发现异常时发出的报警声,具体原因需要结合 蜂鸣声的长短、次数、频率 来分析。我们可以系统化地排查: 背景 TU229V2 服务器长鸣告警,原因是只插了一条电源,在开机状态下插入第二条电源之后告警消失。 1️⃣ 观察蜂鸣声模式 单长鸣/短鸣:通常表示 电源或风扇故障。 连续短鸣:内存或主板异常。 规律重复的鸣声:CPU、显卡或 BIOS 报警。 不规律或一直响:可能硬件严重故障,需要停机检查。 不同厂商的 BIOS/主板厂商对 beep code...

Check File Exists

Bash Snippets

FILE="/etc/iptables/rules.v4" if [ -f "$FILE" ]; then echo "$FILE exists" else echo "$FILE empty" fi

programming-languages
snippet

Check Command Exists

Bash Snippets

if which iptables-save >/dev/null 2>&1; then echo "exists" else echo "empty" fi

programming-languages
snippet

Traffic Stats

Linux Networking

iftop apt-get update apt-get install iftop iftop -i eth1 -P tcpdump BytesMBtcpdump -i eth1 -nn -q -c 5000 | \ awk ' { # 去掉目标端口末尾冒号 gsub(":", "", $5) # 拆分源和目标 split($3, a, "."); split($5, b, ".") src_ip = a[1]"."a[2]"."a[3]"."a[4] ...

tcpdump
iftop
linux

tcpdump

Linux Networking

Specify Port & Flags tcpdump -i lo -nn -s 0 tcp port 9004 and '(tcp[tcpflags] & (tcp-syn|tcp-rst|tcp-ack) != 0)' -i lo:在本地回环接口 (lo) 上抓包,也就是抓取本机进程之间的 TCP 通信。 -nn:不对地址和端口做反向解析(直接显示数字 IP 和端口号)。 -s 0:设置抓取长度为 0,表示抓取整个数据包(默认只抓前 262 字节)。 tcp port 9004:只抓取目标端口 9004...

linux
networking
tcpdump

Installation

MySQL Quick Start

MySQL Client 到 Oracle 官方 MySQL APT repo 下载配置包(最新版在 2025 之前是 0.8.33 这一支): wget https://dev.mysql.com/get/mysql-apt-config_0.8.33-1_all.deb dpkg -i mysql-apt-config_0.8.33-1_all.deb 安装过程中会弹出一个选择界面: 选 MySQL Server & Cluster (Currently selected: mysql-x.x) 里面会...

mysql
installation

Datasource Error

Grafana Troubleshooting

Errors 根据时间排查错误日志docker logs grafana | grep '2025-08-28T05:22:' Grafana 原始日志logger=datasources t=2025-08-28T05:22:51.256384159+08:00 level=error msg="Failed getting data source" err="database is locked" uid=eeichsmn74t8gf id=0 name= orgId=1 logger=sqlstore....

middleware
grafana

MyDumper

MySQL Tools

https://mydumper.github.io/mydumper/docs/html/index.html Installation macOS brew install mydumper

database
mysql
mydumper

Quick Count

MySQL Quick Start

使用最小覆盖索引 针对 InnoDB 表(几十万到几百万行)快速统计行数,可以有几个方法。下面按实用性和效率排序: 选择最窄的索引列(最好是整型或短列)进行扫描,不访问表数据页。 假设你有一个 updated_at 的索引: SELECT COUNT(updated_at) FROM cert; 优化器会用覆盖索引,只扫描索引页,比全表扫描快很多。 如果想强制使用: SELECT COUNT(updated_at) FROM cert USE INDEX (idx_updated_at); 注意:不...

database
mysql
count

pt-table-checksum

MySQL Tools

Installation apt-get -y install percona-toolkit Priviledges 目标库 GRANT SELECT ON foo.* TO 'pttable'@'%'; 校验结果库 GRANT CREATE, INSERT, UPDATE, DELETE ON percona.* TO 'pttable'@'%'; 其它权限 GRANT PROCESS, REPLICATION CLIENT, REPLICATION SLAVE ON *.* TO 'pttable'@...

database
mysql
pt-table