Stateful NAT64 Run
This document explains how to run Jool in Stateful NAT64 mode.
Software-wise, only a successful install of the kernel module is required. The userspace application is not needed in this basic run.
All the remarks in the first document’s Sample Network section apply here.
Nodes A through E:
Nodes V through Z:
Notice these nodes do not need a default route. This is a consequence of them being in the same network as the NAT64; T will be masking the IPv6 nodes, so V through Z think they’re talking directly to it.
In previous versions of Jool, T used to need two or more IPv4 addresses. Because pool4 now stores port ranges, this is no longer the case.
Remember you might want to cross-ping T vs everything before continuing.
This is the insertion syntax:
user@T:~# /sbin/modprobe [--first-time] jool \ [pool6=<IPv6 prefix>] \ [pool4=<IPv4 prefixes>] \ [disabled]
See Kernel Module Options for a description of each argument.
The result looks like this:
user@T:~# /sbin/modprobe --first-time jool pool6=64:ff9b::/96
Jool will append and remove prefix
In previous versions of Jool,
pool4used to be mandatory. This is no longer the case.
Because we skipped the
pool4argument, Jool will fall back to mask packets using the upper ports of
203.0.113.1. Unless you have few IPv6 clients, this is probably not what you want. See pool4 for details on how to fine-tune this.
If something doesn’t work, try the FAQ.
Test by sending requests from the IPv6 network:
Obviously, users should not need to be aware of IP addresses, much less know they need to append a prefix whenever they need to speak to IPv4. The DNS64 document will tell you how to make the prefix-address-hack transparent to users.
Because a NAT64 is stateful, only IPv6-started tests can be run at this point. See port forwarding if 4-to-6 translation is relevant for you.
To shut down Jool, revert the modprobe using the
- More complex setups might require you to consider the MTU notes.
modprobeinsertion and removal mechanism is fine if all you need is a simple single NAT64, but if you want to enclose it in a network namespace, or need multiple Jool instances in a single machine, check out
- Please note that none of what was done in this tutorial survives reboots! Documentation on persistence will be released in the future.
The next tutorial explains DNS64.