FAQ

What is iocage?

iocage is a jail management program designed to simplify jail administration tasks.

What is a jail?

A Jail is a FreeBSD OS virtualization technology allowing users to run multiple copies of the operating system. Some operating systems use the term Zones or Containers for OS virtualization.

What is VNET?

VNET is an independent, per jail virtual networking stack.

How do I configure network interfaces in a VNET or shared IPjail?

Both are configured in the same way: iocage set ip4_add="[interface]|[IP]/[netmask]" [UUID | NAME]. For more info, please refer to the Networking section of this documentation.

Do I need to set my default gateway?

Only if VNET is enabled. You need to assign an IP address to the bridge where the jail interface is attached. This IP essentially becomes the default gateway for your jail.

Can I run a firewall inside a jail?

Yes, a VNET jail supports IPFW. PF is not supported inside the jail. However, you can still enable PF for the host. If you plan to use IPFW inside a jail, be sure securelevel is set to 2.

Can I enable both IPFW and PF at the same time?

Yes, make sure you allow traffic on both in/out for your jails.

Can I create custom jail templates?

Yes, and thin provisioning is supported too!

What is a jail clone?

Clones are ZFS clones. These are fully writable copies of the source jail.

Can I limit the CPU and Memory use?

Yes, but only for legacy versions of iocage. Refer to the iocage.8 manual page or Resource Limits (Legacy ONLY) section of this documentation for more details.

Is there a way to display resource consumption?

Yes - iocage df

Is NAT supported for jails?

Yes. NAT is built into FreeBSD. Treat your server as a core router/firewall. Check the FreeBSD Firewalls chapter for more details.

Will iocage work on a generic system with no ZFS pools?

No. ZFS is a must. If you run a FreeBSD server, you should be using ZFS!

Is ZFS jailing supported?

Yes, please refer to the iocage.8 manual page.