Lxc

LXC Notizen

• LXC auf Ubuntu 14.04-2 LTS
• LXC auf CentOS 7
• LXC Routed Setup 2019

Host Allgemein

Passwort im Container setzen

Passwörter können vom Host aus bequem mit chroot gesetzt werden

 cd /var/lib/lxc/CONTAINER
 chroot rootfs /bin/bash
 passwd

Container Allgemein

Die Netzwerkeinstellungen und der Hostname des Containers können automatischüber die config erzeugt werden 
Im Container:

 rm /etc/network/interfaces
 rm /etc/hostname

In der Containerconfig:

 vim /var/lib/lxc/CONTAINER/config
 lxc.network.type = veth
 lxc.network.flags = up
 lxc.network.link = lxcbr0 # Unter Debian benutzen wir br0
 lxc.network.hwaddr = XX:XX:XX:XX:XX:XX
 lxc.network.ipv4 = XXX.XXX.XXX.XXX/32 # IP des Containers
 lxc.network.ipv4.gateway = XXX.XXX.XXX.XXX # IP des Hosts

Host Ubuntu 14.04

Container mit Systemd starten

Anpassen der Config des Containers

Fehlermeldung verursacht von Apparmor:
Failed to mount cgroup at /sys/fs/cgroup/systemd: Permission denied       

 vim /var/lib/lxc/CONTAINER/config
 lxc.kmsg = 0
 lxc.aa_profile = unconfined

Installation eines Containers

cd /var/lib/lxc
lxc-create -t download -n  ncphp73  -- --dist ubuntu --release bionic --arch amd64
cp  /var/lib/lxc/ncphp73/config  /var/lib/lxc/ncphp73/config.original20190418
vim /var/lib/lxc/ncphp73/config

lxc-ls -f
lxc-start -n ncphp73 
lxc-ls -f
lxc-attach -n ncphp73

Konfiguration

echo "nameserver 8.8.8.8" >> /etc/resolv.conf

vim /etc/bash.bashrc 
# bash-completion auskommentieren

Installation von Software

apt-get update
apt-get install wget bash-completion zip unzip rsync openssh-server openssh-sftp-server

Ex-Kurs apache mit php 7.3

apt-get install software-properties-common
add-apt-repository ppa:ondrej/php
add-apt-repository ppa:ondrej/apache2
apt-get update 
apt-get install php7.3 php7.3-cli php7.3-common
apt-get install imagemagick apache2 libapache2-mod-php7.3 php7.3-cli php7.3 php7.3-common php7.3-imap php7.3-intl php7.3-mysql php7.3-readline php7.3-soap php7.3-zip php7.3-zip php7.3-gd php7.3-xml php7.3-gd php7.3-json php7.3-opcache php-imagick php7.3-curl php7.3-mbstring php7.3-bcmath php7.3-gmp php7.3-zip composer php7.3-curl php7.3-dev php7.3-gd php7.3-mbstring php7.3-zip php7.3-mysql php7.3-xml php7.3-fpm libapache2-mod-php7.3 php7.3-imagick php7.3-recode php7.3-tidy php7.3-xmlrpc php7.3-intl mysql-server-5.7 phpmyadmin apache2-utils

• mysql: Besonderheiten beim root Passwort

Konfiguration von Software

a2enmod ssl
systemctl restart apache2

LXC Probleme

apparmor in lxc3

Lösung in LXC Host

vim /var/lib/lxc/anc_ox/config
# folgendes muss rein
lxc.apparmor.profile = generated
lxc.apparmor.allow_nesting = 1

apache

• Fehlermeldung

systemctl status apache2.service

● apache2.service - The Apache HTTP Server
   Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Wed 2019-12-18 14:58:03 UTC; 1min 19s ago
     Docs: https://httpd.apache.org/docs/2.4/
  Process: 204 ExecStart=/usr/sbin/apachectl start (code=exited, status=226/NAMESPACE)

Dec 18 14:58:03 ancox systemd[1]: Starting The Apache HTTP Server...
Dec 18 14:58:03 ancox systemd[204]: apache2.service: Failed to set up mount namespacing: Perm
ission denied
Dec 18 14:58:03 ancox systemd[204]: apache2.service: Failed at step NAMESPACE spawning /usr/s
bin/apachectl: Permission denied
Dec 18 14:58:03 ancox systemd[1]: apache2.service: Control process exited, code=exited, statu
s=226/NAMESPACE
Dec 18 14:58:03 ancox systemd[1]: apache2.service: Failed with result 'exit-code'.
Dec 18 14:58:03 ancox systemd[1]: Failed to start The Apache HTTP Server.

• Lösung im Lxc Container

vim /etc/systemd/system/multi-user.target.wants/apache2.service
PrivateTmp=true #aus kommentieren 

systemctl daemon-reload
systemctl restart  apache2.service

• https://debianforum.de/forum/viewtopic.php?t=173972

• Lösung in LXC Host

siehe oben lxc#Lösung in LXC Host

mariadb

• Fehlermeldung

systemctl status mariadb.service
● mariadb.service - MariaDB 10.3.18 database server
   Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Wed 2019-12-18 15:04:01 UTC; 5s ago
     Docs: man:mysqld(8)
           https://mariadb.com/kb/en/library/systemd/
  Process: 211 ExecStartPre=/usr/bin/install -m 755 -o mysql -g root -d /var/run/mysqld (code=exited, status=
226/NAMESPACE)

Dec 18 15:04:01 ancox systemd[1]: Starting MariaDB 10.3.18 database server...
Dec 18 15:04:01 ancox systemd[211]: mariadb.service: Failed to set up mount namespacing: Perm
ission denied
Dec 18 15:04:01 ancox systemd[211]: mariadb.service: Failed at step NAMESPACE spawning /usr/b
in/install: Permission denied
Dec 18 15:04:01 ancox systemd[1]: mariadb.service: Control process exited, code=exited, statu
s=226/NAMESPACE
Dec 18 15:04:01 ancox systemd[1]: mariadb.service: Failed with result 'exit-code'.
Dec 18 15:04:01 ancox systemd[1]: Failed to start MariaDB 10.3.18 database server.

• Lösung im Lxc Container

vim /etc/systemd/system/multi-user.target.wants/mariadb.service 
# folgendes erstmal auskommentieren
# ProtectSystem=full
# PrivateDevices=true
# ProtectHome=true

systemctl daemon-reload
systemctl restart mariadb.service

• https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=920643

• Lösung in LXC Host

siehe oben lxc#Lösung in LXC Host

lxc beschränken CPU & MEMORY

1. in lxc Container config

/var/lib/lxc/$CONTAINERNAME/config

# CPUs setzen
lxc.cgroup.cpuset.cpus=1,3
#Max MEMORY setzen
lxc.cgroup.memory.limit_in_bytes = 8096M

# Check im Container Anzahl CPU
cat /proc/cpuinfo | grep processor
processor       : 0
processor       : 1

# Check im Container Anzahl MEMORY
free -m
              total        used        free      shared  buff/cache   available
Mem:           8096         373        7706           2          15        7722
Swap:             0           0           0

unter ubuntu 20.04

hat erst funktioniert nach installation von:

apt-get install lxcfs