Jadm is FreeBSD jail administration tool

Overview

JADM (“jail admin”) is a Python-based framework for end-to-end FreeBSD jail management that builds on your existing /etc/jail.conf while transparently adding ZFS and VNET capabilities:

  • Unified configuration parsing Reads your /etc/jail.conf, interprets both global and per-jail stanzas, and emits an extended internal representation that drives all subsequent actions (raw.githubusercontent.com).

  • ZFS-backed jail homes Creates and manages ZFS datasets under a configurable pool (default zroot/jails), including special “BASE” skeleton models:

    • A read-only dataset (./BASE/) holding shared bits,
    • A writable template (./BASE-SKELETON/) used for new BASE jails, and
    • Per-jail read-write datasets (./BASE-RW/ and ./BASE-jailname/) subject to quotas and snapshot/restore workflows (raw.githubusercontent.com).

  • VNET networking with bridge + epair For each VNET jail, JADM:

    1. Creates an epair device pair,
    2. Attaches one end to a host bridge (e.g. bridge1, which must carry at least one gateway IP),
    3. Moves the other into the jail’s private network stack,
    4. Assigns the jail’s IP/netmask and installs a default route via the bridge gateway,
    5. Tears it down cleanly on stop (raw.githubusercontent.com).

  • Multiple jail types & template cloning

    • VNET (isolated network stack)
    • Host IP (uses any host-assigned address)
    • BASE (skeleton models for standardized environments)
    • Normal (built via bsdinstall, source tree, or existing templates) When cloning from a template, JADM uses ZFS send/receive of snapshots and replicates local settings, avoiding direct ZFS clone dependencies (raw.githubusercontent.com).

  • Comprehensive CLI Commands include:

    initsetup   setup      create      modify      destroy
remove      migrate    snap        start       stop
reboot      shell      list/jls    gateways    log
help        about      verbose     quit/exit

    — with migrate using an AES-encrypted socket plus SSH for ZFS replication, and full support for incremental updates and remote transfers (raw.githubusercontent.com).

  • Seamless integration Produced jails remain fully compatible with standard tools (jexec, service jail, etc.), and JADM references upstream man pages (jail(8), jail.conf(5), zfs(8), ifconfig(8), bridge(4)) for anything outside its scope (raw.githubusercontent.com).

For the complete list of options, configuration examples, and extended usage notes, see the jadm(8) manual or run:

jadm help

Quick start:

Custom FreeBSD kernel for vnet support:

    options VIMAGE

If are not installed:

    pkg install python27 pkg install py27-pip

Install via setup.py:

    ./setup.py build ./setup.py install

Create FreeBSD bridge interface and assign ip address:

    ifconfig bridge1 create ifconfig bridge1 192.168.1.1/24 ifconfig bridge1 alias 10.10.10.1/24 etc ..

IPFW Nat setup:

    ipfw add divert 8668 ip from any to any via (external interface)

Example FreeBSD config:

/etc/rc.conf

    cloned_interfaces="bridge1" ipv4_addrs_bridge1="192.168.1.1/24 10.10.10.1/24"

    gateway_enable=”YES”
    arpproxy_all=”NO”

    firewall_enable=”YES”
    firewall_script=”/etc/ipfw.conf”
    natd_enable=”YES”
    natd_flags=”-f /etc/natd.conf”

    jail_enable=”YES”
    jail_parallel_start=”YES”
    jail_list=”firstjaisl secondjail “

/etc/natd.conf

    interface (external interface) dynamic yes same_ports yes

/etc/ipfw.conf

    #!/bin/sh

    fwcmd=”/sbin/ipfw -q”
    eif=”(external interface)”

    ${fwcmd} -f flush

    ${fwcmd} add 65532 divert natd ip from any to any via ${eif}

CURRENT VERSION:

FreeBSD port source:

Tags: jails freebsd