show how to fix ip address misconfigs with fabric

tsa/howto/new-machine.mdwn

@@ -67,14 +67,20 @@ taken by the installer:
  2. a hostname has been set, picked from the [[doc/naming-scheme]]
 
  3. a public IP address has been set and the host is available over
-    SSH on that IP address
+    SSH on that IP address. this can be fixed with:
+
+        fab -H root@88.99.194.57 host.rewrite-interfaces 88.99.194.57 26 88.99.194.1 2a01:4f8:221:2193::2 64 fe80::1
 
  4. the machine has a short hostname (e.g. `test`) which resolves to a
     fully qualified domain name (e.g. `test.torproject.org`) in the
-    `torproject.org` domain (i.e. `/etc/hosts` is correctly configured)
-
- 5. DNS works on the machine (i.e. `/etc/resolv.conf` is correctly
-    configured)
+    `torproject.org` domain (i.e. `/etc/hosts` is correctly
+    configured). this can be fixed with:
+    
+        fab -H root@88.99.194.57 host.rewrite-hosts fsn-node-05.torproject.org 88.99.194.57
+
+ 5. DNS works on the machine (i.e. `/etc/resolv.conf` is configured to
+    talk to a working resolver, but not necessarily ours, which Puppet
+    will handle)
 
  6. a root password has been set in the password manager (TODO: move
     to trocla?  [#33332](https://trac.torproject.org/projects/tor/ticket/33332))