howto/upgrades: fix link

howto/upgrades.md

@@ -187,7 +187,7 @@ the error should no longer appear.
 The `ganeti.service` warning is typically an OpenSSL upgrade that
 affects qemu, and restarting ganeti (thankfully) doesn't restart
 VMs. to Fix this, migrate all VMs to their secondaries and back, see
-[Ganeti reboot procedures](howto/ganeti#rebooting), possibly the [instance-only restart](#instance-only-restarts)
+[Ganeti reboot procedures](howto/ganeti#rebooting), possibly the [instance-only restart](howto/ganeti#instance-only-restarts)
 procedure.
 
 ## Open vSwitch