migrate new-machine docs to swap file (team#41188)

howto/ganeti.md

@@ -44,7 +44,7 @@ See also the more extensive [glossary in the Ganeti documentation](http://docs.g
 ## Adding a new instance
 
 This command creates a new guest, or "instance" in Ganeti's
-vocabulary with 10G root, 2G swap, 20G spare on SSD, 800G on HDD, 8GB
+vocabulary with 10G root, 512M swap, 20G spare on SSD, 800G on HDD, 8GB
 ram and 2 CPU cores:
 
     gnt-instance add \
@@ -54,9 +54,8 @@ ram and 2 CPU cores:
       --no-ip-check \
       --no-name-check \
       --disk 0:size=10G \
-      --disk 1:size=2G,name=swap \
-      --disk 2:size=20G \
-      --disk 3:size=800G,vg=vg_ganeti_hdd \
+      --disk 1:size=20G \
+      --disk 2:size=800G,vg=vg_ganeti_hdd \
       --backend-parameters memory=8g,vcpus=2 \
       test-01.torproject.org
 
@@ -69,9 +68,8 @@ This configures the following:
    (even with `--no-wait-for-sync` there are some operations that block on
    synced mirrors).  Only one node should be provided as the argument for
    `--node` then.
- * three partitions: one on the default VG (SSD), one on another (HDD)
-   and a swap file on the default VG, if you don't specify a swap device,
-   a 512MB swapfile is created in `/swapfile`. TODO: configure disk 2
+ * two additional partitions: one on the default VG (SSD), one on another
+   (HDD). A 512MB swapfile is created in `/swapfile`. TODO: configure disk 2
    and 3 automatically in installer. (`/var` and `/srv`?)
  * 8GB of RAM with 2 virtual CPUs
  * an IP allocated from the public gnt-fsn pool:
@@ -131,8 +129,7 @@ This is a typical server creation in the `gnt-chi` cluster:
       --no-ip-check \
       --no-name-check \
       --disk 0:size=10G \
-      --disk 1:size=2G,name=swap \
-      --disk 2:size=20G \
+      --disk 1:size=20G \
       --backend-parameters memory=8g,vcpus=2 \
       test-01.torproject.org
 
@@ -146,7 +143,6 @@ DRBD, in the FSN cluster:
           --no-ip-check \
           --no-name-check \
           --disk 0:size=10G \
-          --disk 1:size=2G,name=swap \
           --backend-parameters memory=1g,vcpus=1 \
           test-01.torproject.org
 
@@ -161,8 +157,7 @@ A test server in `gnt-dal`:
       --no-ip-check \
       --no-name-check \
       --disk 0:size=10G \
-      --disk 1:size=2G,name=swap \
-      --disk 2:size=20G \
+      --disk 1:size=20G \
       --backend-parameters memory=8g,vcpus=2 \
       test-01.torproject.org
 
@@ -3366,8 +3361,8 @@ as possible. The installer will:
  2. setup and log a random root password
  3. make sure SSH is installed and log the public keys and
     fingerprints
- 4. setup swap if a labeled partition is present, or a 512MB swapfile
-    otherwise
+ 4. create a 512MB file-backed swap volume at `/swapfile`, or
+    a swap partition if it finds one labeled `swap`
  5. setup basic static networking through `/etc/network/interfaces.d`
 
 We have custom configurations on top of that to: