ALPINE LINUX QUICK REFERENCE
Package management, services, networking, Docker base image
Package Management
apk Basics
apk update # refresh package index
apk upgrade # upgrade all packages
apk add curl git vim # install packages
apk del curl # remove a package
apk search nginx # search for packages
Package Info
apk info # list installed packages
apk info -a nginx # detailed package info
apk info -L nginx # list files in package
apk policy nginx # show available versions
Virtual Packages
# Install build deps as a group, remove later
apk add --virtual .build-deps gcc musl-dev
make && make install
apk del .build-deps
Repositories
# /etc/apk/repositories
https://dl-cdn.alpinelinux.org/alpine/v3.20/main
https://dl-cdn.alpinelinux.org/alpine/v3.20/community
@edge https://dl-cdn.alpinelinux.org/alpine/edge/testing
Services
OpenRC Service Management
rc-service nginx start # start service
rc-service nginx stop # stop service
rc-service nginx restart # restart service
rc-service nginx status # check status
Runlevel Management
rc-update add nginx default # enable at boot
rc-update del nginx default # disable at boot
rc-update show # list all services
rc-status # show running services
Runlevels
| sysinit | System initialization (filesystems, clock) |
| boot | Basic system services (networking, syslog) |
| default | Normal services (web servers, daemons) |
| shutdown | Shutdown tasks |
Configuration
Key Config Files
| /etc/apk/repositories | Package repository URLs |
| /etc/hostname | System hostname |
| /etc/network/interfaces | Network interface config |
| /etc/conf.d/ | Service-specific configuration |
| /etc/motd | Message of the day |
System Setup
setup-alpine # interactive full setup
setup-timezone # set timezone
setup-keymap # configure keyboard layout
setup-hostname myhost # set hostname
Timezone
apk add tzdata
cp /usr/share/zoneinfo/US/Eastern /etc/localtime
echo "US/Eastern" > /etc/timezone
apk del tzdata # optional: remove to save space
Networking
Interface Config
# /etc/network/interfaces
auto eth0
iface eth0 inet dhcp
# --- static ---
iface eth0 inet static
address 192.168.1.10/24
gateway 192.168.1.1
Network Commands
ip addr show # show IP addresses
ip route show # show routing table
ip link set eth0 up # bring interface up
setup-interfaces # interactive net config
DNS & Firewall
# DNS: /etc/resolv.conf
nameserver 1.1.1.1
nameserver 8.8.8.8
# Firewall
apk add iptables
iptables -L -n # list rules
Users
User Management
adduser alice # create user (interactive)
adduser -D -s /bin/sh bob # non-interactive, set shell
deluser alice # delete user
passwd alice # set/change password
Groups & Sudo
addgroup devs # create group
addgroup alice devs # add user to group
apk add doas # lightweight sudo alternative
# /etc/doas.conf
permit persist alice as root
System Users
adduser -S -D -H -s /sbin/nologin myapp
# -S system user -D no password
# -H no home dir -s no shell
Disk & Storage
Filesystem Commands
df -h # disk usage summary
du -sh /var/log # directory size
lsblk # list block devices
mount /dev/sda1 /mnt # mount device
umount /mnt # unmount
LBU (Alpine Local Backup)
# For diskless/data modes — persist changes across reboots
lbu status # show uncommitted changes
lbu commit # save changes to boot media
lbu list # list backed-up files
lbu include /etc/myconf # add path to backup
Disk Setup
setup-disk # interactive disk install
setup-disk /dev/sda # install to specific disk
# Modes: sys (traditional), data, diskless
Docker Base Image
Why Alpine for Docker
| ~5 MB base image | vs ~80 MB for Debian slim |
| musl libc | Smaller than glibc (some compat issues) |
| apk package manager | Fast, no cache by default |
| Minimal attack surface | Fewer packages = fewer CVEs |
Minimal Dockerfile
FROM alpine:3.20
RUN apk add --no-cache python3 py3-pip
COPY app.py /app/
CMD ["python3", "/app/app.py"]
Multi-Stage Build
FROM golang:1.22-alpine AS builder
WORKDIR /src
COPY . .
RUN go build -o /app
FROM alpine:3.20
COPY --from=builder /app /app
CMD ["/app"]
Common Gotchas
| --no-cache | Always use to keep image small |
| musl vs glibc | Some binaries need gcompat package |
| No bash by default | Use /bin/sh or apk add bash |
| Timezone missing | Install tzdata if needed |
Common Patterns
Install Build Tools
apk add --no-cache build-base # gcc, make, etc.
apk add --no-cache python3-dev # Python headers
apk add --no-cache linux-headers # kernel headers
Cron Jobs
# Add a cron job
echo "*/5 * * * * /usr/local/bin/task.sh" \
| crontab -
rc-service crond start
rc-update add crond default
Enable SSH
apk add openssh
rc-service sshd start
rc-update add sshd default
# Config: /etc/ssh/sshd_config
Upgrade Alpine Version
# Edit /etc/apk/repositories: change v3.19 → v3.20
apk update
apk upgrade --available
sync && reboot