- After reinstalling Yggdrasil, use `load` to reload your configuration and then `commit` to make it effective again. Do not run `save` under any circumstances until after you have reloaded your configuration.
Start by either [downloading the latest vyatta-yggdrasil .deb package](https://circleci.com/api/v1.1/project/github/yggdrasil-network/yggdrasil-go/latest/artifacts) and install it:
```
sudo dpkg -i vyatta-yggdrasil-x.x.xxx-mipsel.deb
```
## Generate configuration
Configuration for Yggdrasil is generated automatically when you create an interface.
```
configure
set interfaces yggdrasil tun0
commit
```
At this point, Yggdrasil will start running using default configuration.
If you want to allow other IPv6 hosts on your network to communicate through yggdrasil, you can configure an IPv6 masquerade rule. All traffic sent from other hosts on the network through the Yggdrasil interface will be NAT'd.
set interfaces yggdrasil tun0 masquerade from xxxx:xxxx:xxxx::/48
commit
```
If you have multiple IPv6 subnets, then they can be configured individually by setting multiple `masquerade from` source ranges. Both private/ULA and public IPv6 subnets are acceptable.
Use this as an example firewall configuration, which will allow outgoing connections but prevent unexpected incoming ones, with the exception of ICMPv6 which will be allowed: