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Python install module issues

I can’t install python-ldap python-ldap https://www.python-ldap.org/en/latest/installing.html $ pip install python-ldap In file included from Modules/LDAPObject.c:9: Modules/errors.h:8: fatal error: lber.h: No such file or directory Debian/Ubuntu: sudo apt-get install libsasl2-dev python-dev libldap2-dev libssl-dev RedHat/CentOS: sudo yum install python-devel openldap-devel sudo yum groupinstall "Development tools" molecule $ pip install molecule error: command 'gcc' failed with exit status 1 ---------------------------------------- Command "/usr/bin/python2 -u -c "import setuptools, tokenize;__file__='/tmp/pip-install-I5DGC3/psutil/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /tmp/pip-record-Fy7V4X/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /tmp/pip-install-I5DGC3/psutil/ RedHat/CentOS: yum -y install gcc gcc-c++ kernel-devel yum -y install python-devel libxslt-devel libffi-devel openssl-devel ansible $ pip install ansible ImportError: No module named pkg_resources yum install -y python-setuptools import pandas ModuleNotFoundError: No module named '_bz2' apt-get install -y libbz2-dev yum install -y bzip2-devel from .cv2 import * ImportError: libSM.so.6: cannot open shared object file: No such file or directory ImportError: libXrender.so.1: cannot open shared object file: No such file or directory ImportError: libXext.so.6: cannot open shared object file: No such file or directory Ubuntu: apt-get install libsm6 apt-get install libxrender1 apt-get install libxext-dev CentOS: yum install libSM yum install libXrender-devel yum install libXext

Wednesday, March 4, 2020 Read

vagrant筆記

vagrant 筆記 Vagrant+virtualbox (2): 實戰封裝自制 package.box Vagrant 學習筆記 1 General 1.1 Path 下載的 box 預設放在~/.vagrant.d/boxes 裡 guest machine 的 data 放的地方根據 VM 設定而不同可開啟 VirtualBox 查看，VirtualBox 預設是在~/VirtualBox\ VMS 1.2 Shared Folder guest machine 的/vagrant 將會自動 mount 到 host machine 的放 Vagrantfile 的那個 folder 此功能需要 guest machine 的 Box 的 VB guest additions 版本與 VM 中的一樣若出現錯誤則需要更新 box 或用這個非官方的 plugin: https://github.com/dotless-de/vagrant-vbguest 2 Uninstall 2.1 REMOVING THE VAGRANT PROGRAM rm -rf /Applications/Vagrant rm -f /usr/bin/vagrant sudo pkgutil --forget com.vagrant.vagrant 2.2 REMOVING USER DATA rm -rf ~/.vagrant.d 3 Command https://www.vagrantup.com/docs/cli/

Wednesday, February 26, 2020 Read

Cannot set command timeout per task with network_cli

Cannot set command timeout per task with network_cli Ansible 的委托并发和任务超时 - name: run command ios_command: commands: - show version vars: ansible_command_timeout: 40

Tuesday, January 14, 2020 Read

How to Create Temporary Files in Bash: mktemp and trap

How to Create Temporary Files in Bash: mktemp and trap mktemp command The generated temp file name is random and readable/writable only by the user. To ensure creation succeeds, append OR (||) after mktemp to exit on failure. To delete temp files on script exit, use trap to register cleanup. #!/bin/bash trap 'rm -f "$TMPFILE"' EXIT TMPFILE=$(mktemp) || exit 1 echo "Our temp file is $TMPFILE" mktemp options -d creates a temporary directory. -p specifies the directory for temp files. Default is $TMPDIR. If not set, /tmp is used. -t specifies a filename template. The template must end with at least three consecutive X characters for randomness; six X are recommended. The default template is tmp. followed by ten random characters. trap usage The trap command handles system signals in Bash scripts.

Monday, December 30, 2019 Read

Getting Started with GitHub Actions

Monday, December 23, 2019 Read

How Does Nginx Defend Against DDoS?

How Does Nginx Defend Against DDoS? Nginx limit module for access rate and max concurrent connections (DDoS protection) ngx_http_limit_req_module limit_req_zone $binary_remote_addr zone=mylimit:10m rate=10r/s;

Friday, December 20, 2019 Read

Golang Service Exceeded File Handle Limit (too many open files)

Golang Service Exceeded File Handle Limit (too many open files) Check system config: ulimit -a | grep open. The system config is normal. Check the service file limit: cat /proc/40636/limits. The service did not inherit the system settings and is still limited to 1024. Check open file count: lsof -p 40636 | wc -l. It exceeds the limit, so the error occurs. Check which connections are open: lsof -p 40636 > openfiles.log. Many HTTP connections were left open to the alerting service. The root cause is that the app failed to parse config, sent errors to the alerting service, and did not close connections, leading to too many open files. Why it did not inherit system limits needed more investigation.

Monday, December 16, 2019 Read

Trellis Ansible Bad Interpreter Error

Trellis Ansible Bad Interpreter Error Bad Interpreter Error Error we got using Ansible was a bad interpreter error. Python 2.7 is not to be found: zsh: /usr/local/bin/ansible-vault: bad interpreter: /usr/local/opt/python@2/bin/python2.7: no such file or directory And that was correct because when we checked /usr/local/opt we only had Python 3. Installation Python 2 brew install python@2 Python Crashing Hard Next, on Ansible version check I got another error ➜ trellis git:(master) ansible --version [1] 19153 abort ansible --version It was somehow crashing Python 2.7 though it should just work with it. I decided to upgrade Ansible as well

Friday, December 6, 2019 Read

Load Balancing with iptables and ip rule

Load Balancing with iptables and ip rule Steps This example uses an Arch Linux device with two Internet uplinks: eth0 and eth1. The mapping is: Mark 10 (0xa) - Routing table #110 - use eth0 Mark 11 (0xb) - Routing table #111 - use eth1 We decide which uplink to use based on the packet mark. First, use ip rule to map each mark to its routing table. The default routing table priority is 32768. To ensure our tables are used, set a higher priority (for example 31000).

Wednesday, December 4, 2019 Read

htop explained

Thursday, November 14, 2019 Read

Some Jenkinsfile examples

Some Jenkinsfile examples Parallel #!/usr/bin/env groovy pipeline { agent any stages { stage("Build") { steps { sh 'mvn -v' } } stage("Testing") { parallel { stage("Unit Tests") { agent { docker 'openjdk:7-jdk-alpine' } steps { sh 'java -version' } } stage("Functional Tests") { agent { docker 'openjdk:8-jdk-alpine' } steps { sh 'java -version' } } stage("Integration Tests") { steps { sh 'java -version' } } } } stage("Deploy") { steps { echo "Deploy!" } } } } When #!/usr/bin/env groovy pipeline { agent any environment { VALUE_ONE = '1' VALUE_TWO = '2' VALUE_THREE = '3' } stages { // skip a stage while creating the pipeline stage("A stage to be skipped") { when { expression { false } //skip this stage } steps { echo 'This step will never be run' } } // Execute when branch = 'master' stage("BASIC WHEN - Branch") { when { branch 'master' } steps { echo 'BASIC WHEN - Master Branch!' } } // Expression based when example with AND stage('WHEN EXPRESSION with AND') { when { expression { VALUE_ONE == '1' && VALUE_THREE == '3' } } steps { echo 'WHEN with AND expression works!' } } // Expression based when example stage('WHEN EXPRESSION with OR') { when { expression { VALUE_ONE == '1' || VALUE_THREE == '2' } } steps { echo 'WHEN with OR expression works!' } } // When - AllOf Example stage("AllOf") { when { allOf { environment name:'VALUE_ONE', value: '1' environment name:'VALUE_TWO', value: '2' } } steps { echo "AllOf Works!!" } } // When - Not AnyOf Example stage("Not AnyOf") { when { not { anyOf { branch "development" environment name:'VALUE_TWO', value: '4' } } } steps { echo "Not AnyOf - Works!" } } } }

Wednesday, November 6, 2019 Read

Jinja docx template, avoiding new line in nested for

Tuesday, October 29, 2019 Read