# Tech Skills

## Linux
Troubleshooting user cannot login issue:
Invesitgation from :
* sssd, pam, nofile (limitation setup), ldap
* HDD broken
* service broken
* network connection

Troubleshooting DNS issues:
* Truncate
* DNS route (dig, tcpdump trace package)
* Zone management

Filesystem:
* have study on filesystem : inode, superblock...etc

Openstack:
* Deployed a server via openstack client
* Status check on baremetal and server instance.
* Basic troubleshooting on openstack: remove faulty instance, list error logs.

Others:
* Uderstand certification configuration.
* Use vim as default editor
* Qemu and kvm

## Ansible
* Dealing with legacy ansible code with 2 repo and 20+ yaml files, extracted necessry files and provide a interface to simplify operations.
* Able to deal with old ansible playbook 2.9.7+
* Able to implement ansible playbook from scratch (2.12+)
* Trcaing ansible builtin module (copy, move..etc)
* My answer on stack overflow: https://stackoverflow.com/questions/24851575/ansible-how-to-pass-multiple-commands/62566158#62566158

## Docker
* Basic docker operation (run, volumn, netwrok, exec and image)
* Understand multi-layer build to reduce image size
* Build integration test and local dev env with docker-compose
* Have a study on namespace, understand docker vs VM.
* Have experience on overlay filesystem.
* Use ansible to deploy docker containers.