From b7fc235b41c4c14a5517d9f9a9c9e7b32ac7d43d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Th=C3=A9o=20Marchal?= <me@theomarchal.com>
Date: Fri, 17 Sep 2021 02:17:23 +0200
Subject: [PATCH] Add git, modify lxc and docker

---
 docker.md | 39 +++++++++++++++++++------------
 git.md    | 13 +++++++++++
 lxc.md    | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 106 insertions(+), 14 deletions(-)
 create mode 100644 git.md
 create mode 100644 lxc.md

diff --git a/docker.md b/docker.md
index 0de2a12..1ffcc8c 100644
--- a/docker.md
+++ b/docker.md
@@ -1,20 +1,31 @@
-Show running containers
-`docker ps`
 
-Show all existing containers
-`docker ps -a`
 
-Access a container
-`docker exec -it CONTAINER bash`
+# Docker
 
-Remove a volume not associated with any container
-`docker volume prune`
+## Manage containers
 
-Start a container from a compose file
-`docker-compose up -d`
+* Start a container from a compose file: `docker-compose up -d`
+* Access a container: `docker exec -it CONTAINER bash`
 
-Backup a database from a container
-`docker exec CONTAINER /usr/bin/mysqldump -u root --password=root DATABASE > backup.sql`
+* Remove a volume not associated with any container: `docker volume prune`
 
-Restore a database to a container
-`cat backup.sql | docker exec -i CONTAINER /usr/bin/mysql -u root --password=root DATABASE`
+## List containers
+
+* Show running containers: `docker ps`
+
+* Show all existing containers: `docker ps -a`
+
+## Database
+
+* Backup a database from a container
+  `docker exec CONTAINER /usr/bin/mysqldump -u root --password=root DATABASE > backup.sql`
+
+* Restore a database to a container
+  `cat backup.sql | docker exec -i CONTAINER /usr/bin/mysql -u root --password=root DATABASE`
+
+## Specifics use
+
+### Nextcloud
+
+* Manage a Nextcloud Docker instance
+  `docker exec -u www-data -it nextcloud-web php occ maintenance:mode --off`
diff --git a/git.md b/git.md
new file mode 100644
index 0000000..d1940c2
--- /dev/null
+++ b/git.md
@@ -0,0 +1,13 @@
+# Git
+
+## Submodules
+
+* Initialize a git submodule after a clone
+  `git submodule update --init --recursive`
+
+* Update a git submodule
+  `git submodule update`
+
+* Update the reference to the last commit in the submodule inside the parent repository
+  `git submodule update --remote --merge`
+
diff --git a/lxc.md b/lxc.md
new file mode 100644
index 0000000..f760280
--- /dev/null
+++ b/lxc.md
@@ -0,0 +1,68 @@
+# LXC
+
+## Create a container
+
+* `$ lxc launch [distribution] [name]`
+    * **example:** `$ lxc launch images:debian/10 test-container`
+
+## List available distribution images
+
+* `$ lxc image list images:`
+
+## List existing containers
+
+* `$ lxc list`
+
+```
++----------------+---------+----------------------+---------------------------+------------+-----------+
+|    NAME        |  STATE  |         IPV4         |            IPV6           |    TYPE    | SNAPSHOTS |
++----------------+---------+----------------------+---------------------------+------------+-----------+
+| alpine         | STOPPED |                      |                           | PERSISTENT | 1         |
++----------------+---------+----------------------+---------------------------+------------+-----------+
+| debian         | STOPPED |                      |                           | PERSISTENT | 0         |
++----------------+---------+----------------------+---------------------------+------------+-----------+
+| ubuntu         | STOPPED |                      |                           | PERSISTENT | 3         |
++----------------+---------+----------------------+---------------------------+------------+-----------+
+| minimal        | RUNNING | 10.10.10.10 (eth0)   | fd80::0000 (eth0)         | PERSISTENT | 0         |
++----------------+---------+----------------------+---------------------------+------------+-----------+
+| test-container | STOPPED |                      |                           | PERSISTENT | 0         |
++----------------+---------+----------------------+---------------------------+------------+-----------+
+```
+
+## Change state
+
+* Start a container: `$ lxc start [container]`
+* Stop a container: `$ lxc stop [container]`
+
+## Access a container
+
+* `$ lxc exec [repository] [command]`
+    * **example:** `$ lxc exec test-container bash`
+
+## Snapshots
+
+* Create a snapshot: `$ lxc snapshot [container] [snapshot_name]`
+    * **example:** `$ lxc snapshot test-container base_state`
+* Restore a snapshot: `$ lxc restore [container] [snapshot_name]`
+    * **example:** `$ lxc restore test-container base_state`
+
+## Copy files
+
+* To a container: `$ lxc file push [/local/files/to/copy] [container]/[destination/path]`
+    * **example:** `$ lxc file push -r /home/user/files test-container/root` (add `-r` to copy a folder)
+* From a container: `$ lxc file pull [container][/files/to/copy] [destination/path]`
+    * **example:** `$ lxc file pull test-container/root/files .` 
+
+## Privileged containers
+
+This feature is only available when LXD is installed.
+
+* When creating a container: `$ lxc launch [distribution] [name] -c security.privileged=true`
+    * Please note that this parameter apparently cannot be changed later.
+
+When a container is privileged, we can share folders from the host to the container, in a **read-write** manner. We can still add a shared folder with unprivileged containers, but they will be **read-only** (chowned at nobody:nobody).
+
+Note that you will need to change the group and user of the folder to the corresponding one of lxd (use `id lxd` to know it) before adding it.
+
+* Adding a shared folder: `$ lxc config device add [container] [share_name] disk source=[/host/path/] path=[/container/path]`
+    * **example:** `$ lxc config device add test-container home_dir disk source=/home/$USER path=/home/ubuntu`
\ No newline at end of file