Document how choose nodes for new Ganeti instances

howto/ganeti.md

@@ -111,6 +111,12 @@ Then follow [howto/new-machine](howto/new-machine).
    This situation is covered by [ticket 33785](https://bugs.torproject.org/33785). If this problem
    occurs, it might be worth [rebalancing the cluster](#rebalancing-a-cluster).
 
+   The following dashboards can help you choose the less busy nodes to use:
+
+   - CPU usage: [gnt-dal](https://grafana.torproject.org/d/gex9eLcWz/cpu-usage?orgId=1&refresh=1m&var-class=role::ganeti::dal&var-node=All&var-show_cpu_count=or), [gnt-fsn](https://grafana.torproject.org/d/gex9eLcWz/cpu-usage?orgId=1&refresh=1m&var-class=role::ganeti::fsn&var-node=All&var-show_cpu_count=or)
+   - Memory usage: [gnt-dal](https://grafana.torproject.org/d/amgrk2Qnk/memory-usage?from=now-24h&to=now&var-class=role::ganeti::dal&var-node=All&var-show_cpu_count=or&orgId=1&refresh=1m), [gnt-fsn](https://grafana.torproject.org/d/amgrk2Qnk/memory-usage?from=now-24h&to=now&var-class=role::ganeti::fsn&var-node=All&var-show_cpu_count=or&orgId=1&refresh=1m)
+   - LVM Disk usage: [gnt-dal](https://grafana.torproject.org/d/f7887271-1a77-4138-ad16-28be8b0ad0ab/lvm-disk-usage?orgId=1&var-class=role::ganeti::dal&var-vg_name=All&var-instance=All), [gnt-fsn](https://grafana.torproject.org/d/f7887271-1a77-4138-ad16-28be8b0ad0ab/lvm-disk-usage?orgId=1&var-class=role%3A%3Aganeti%3A%3Afsn&var-vg_name=All&var-instance=All)
+
  * **ping failure**: there is a bug in `ganeti-instance-debootstrap`
    which misconfigures `ping` (among other things), see [bug
    31781](https://bugs.torproject.org/31781). It's currently patched in our version of the Debian