구차니의 잡동사니 모음

# ll -h

-rw-------. 1 root root 1.1G  6월  3 12:23 generic.qcow2

# file *

generic.qcow2:       QEMU QCOW Image (v3), 1073741824 bytes

# qemu-img resize generic.qcow2 +19G

Image resized.

# ll -h

합계 32G

-rw-------. 1 root root 1.1G  6월  3 12:25 generic.qcow2

# file *

generic.qcow2:       QEMU QCOW Image (v3), 21474836480 bytes

# qemu-img resize generic.qcow2 -19G

qemu-img: qcow2 doesn't support shrinking images yet

qemu-img: This image does not support resize 

이미지는 컨테이너 실행에 필요한 파일과 설정값등을 포함하고 있는 것으로 상태값을 가지지 않고 변하지 않습니다(Immutable). 

컨테이너는 이미지를 실행한 상태라고 볼 수 있고 추가되거나 변하는 값은 컨테이너에 저장됩니다. 

 도커 이미지 생성

$ docker build -t django-sample .

앱 컨테이너를 실행

$ docker run -it --rm \

    -p 8000:8000 \

    django-sample \

    ./manage.py runserver 0:8000

데이터베이스 컨테이너 실행

$ docker run -it --rm \

    postgres:9.6.1

앱 컨테이너를 실행한 후 PostgreSQL 컨테이너를 실행했습니다. 그런데 컨테이너는 실행 직후부터 컨테이너 외부의 상황과 격리됩니다. 따라서 PostgreSQL 컨테이너가 실행되었는지 알지 못하죠.

db 컨테이너를 지우면, 데이터베이스 데이터가 사라짐

docker 단일 컨테이너를 관리합니다.

docker-compose 은 여러 컨테이너 애플리케이션을 관리합니다.

docker-compose의 사용 에는 3 단계가 필요합니다.

Dockerfile을 사용 하여 앱 환경 정의

docker-compose.yml 에 앱 서비스 정의

docker-compose up 실행하여 앱을 시작하고 실행합니다. 

# yum search postgresql

Loaded plugins: fastestmirror, langpacks

Loading mirror speeds from cached hostfile

 * base: mirror.kakao.com

 * extras: mirror.kakao.com

 * updates: mirror.kakao.com

======================================================== N/S matched: postgresql =========================================================

freeradius-postgresql.x86_64 : Postgresql support for freeradius

libreoffice-postgresql.x86_64 : PostgreSQL connector for LibreOffice

pcp-pmda-postgresql.x86_64 : Performance Co-Pilot (PCP) metrics for PostgreSQL

postgresql.i686 : PostgreSQL client programs

postgresql.x86_64 : PostgreSQL client programs

postgresql-contrib.x86_64 : Extension modules distributed with PostgreSQL

postgresql-devel.i686 : PostgreSQL development header files and libraries

postgresql-devel.x86_64 : PostgreSQL development header files and libraries

postgresql-docs.x86_64 : Extra documentation for PostgreSQL

postgresql-jdbc.noarch : JDBC driver for PostgreSQL

postgresql-jdbc-javadoc.noarch : API docs for postgresql-jdbc

postgresql-libs.i686 : The shared libraries required for any PostgreSQL clients

postgresql-libs.x86_64 : The shared libraries required for any PostgreSQL clients

postgresql-odbc.x86_64 : PostgreSQL ODBC driver

postgresql-plperl.x86_64 : The Perl procedural language for PostgreSQL

postgresql-plpython.x86_64 : The Python2 procedural language for PostgreSQL

postgresql-pltcl.x86_64 : The Tcl procedural language for PostgreSQL

postgresql-server.x86_64 : The programs needed to create and run a PostgreSQL server

postgresql-static.i686 : Statically linked PostgreSQL libraries

postgresql-static.x86_64 : Statically linked PostgreSQL libraries

postgresql-test.x86_64 : The test suite distributed with PostgreSQL

postgresql-upgrade.x86_64 : Support for upgrading from the previous major release of PostgreSQL

qt-postgresql.i686 : PostgreSQL driver for Qt's SQL classes

qt-postgresql.x86_64 : PostgreSQL driver for Qt's SQL classes

qt3-PostgreSQL.i686 : PostgreSQL drivers for Qt 3's SQL classes

qt3-PostgreSQL.x86_64 : PostgreSQL drivers for Qt 3's SQL classes

qt5-qtbase-postgresql.i686 : PostgreSQL driver for Qt5's SQL classes

qt5-qtbase-postgresql.x86_64 : PostgreSQL driver for Qt5's SQL classes

PyGreSQL.x86_64 : A Python client library for PostgreSQL

apr-util-pgsql.x86_64 : APR utility library PostgreSQL DBD driver

libdbi-dbd-pgsql.x86_64 : PostgreSQL plugin for libdbi

perl-DBD-Pg.x86_64 : A PostgreSQL interface for perl

php-pgsql.x86_64 : A PostgreSQL database module for PHP

python-psycopg2.x86_64 : A PostgreSQL database adapter for Python

python-psycopg2-debug.x86_64 : A PostgreSQL database adapter for Python 2 (debug build)

python-psycopg2-doc.x86_64 : Documentation for psycopg python PostgreSQL database adapter

redland-pgsql.x86_64 : PostgreSQL storage support for Redland

rhdb-utils.x86_64 : Miscellaneous utilities for PostgreSQL - Red Hat Edition

tcl-pgtcl.x86_64 : A Tcl client library for PostgreSQL

  Name and summary matches only, use "search all" for everything. 

SELECT * FROM pg_catalog.pg_tables; 

SELECT * FROM pg_catalog.pg_tables WHERE tableowner='username;' 

pgAdmin 4 is a complete rewrite of pgAdmin, built using Python and Javascript/jQuery. A desktop runtime written in C++ with Qt allows it to run standalone for individual users, or the web application code may be deployed directly on a webserver for use by one or more users through their web browser. The software has the look and feel of a desktop application whatever the runtime environment is, and vastly improves on pgAdmin III with updated user interface elements, multi-user/web deployment options, dashboards and a more modern design. 

 sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ $(lsb_release -cs)-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'

sudo apt install wget ca-certificates

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add

sudo apt update

sudo apt install pgadmin4

 docker run 명령이 "create" 와 "start" 명령을 한번에 실행시키는 명령