doc update and prune timing

Author: chuckp22

docs/scheduling-backups.md

@@ -1,4 +1,4 @@
-# Scheduling backups
+# Scheduling backups & snapshot pruning
 
 Regular backups should be scheduled using `cron(8)` or similar command
 scheduling service on the backup host. The backup frequency will dictate the
@@ -17,6 +17,13 @@ based on the frequency of backups. The ten most recent snapshots are retained by
 default. The number should be adjusted based on backup frequency and available
 storage.
 
+By default all expired and incomplete snapshots are deleted at the end of the main
+backup process `ghe-backup`. If pruning of these snapshots takes a long time you can
+choose to disable the pruning process from the backup run and schedule it separately.
+This can be achieved by enabling the `GHE_PRUNING_SCHEDULED` option in `backup.config`.
+Please note if this option is enabled, you will need to schedule the pruning script `ghe-prune-snapshots`
+using `cron` or similar command scheduling service on the backup host.
+
 To schedule hourly backup snapshots with verbose informational output written to
 a log file and errors generating an email:
 
@@ -30,5 +37,10 @@ To schedule nightly backup snapshots instead, use:
 
     0 0 * * * /opt/backup-utils/bin/ghe-backup -v 1>>/opt/backup-utils/backup.log 2>&1
 
+To schedule daily snapshot pruning, use:
+
+    [email protected]
+
+    0 3 * * * /opt/backup-utils/share/github-backup-utils/ghe-prune-snapshots 1>>/opt/backup-utils/prune-snapshots.log 2>&1
 
 [1]: https://en.wikipedia.org/wiki/Recovery_point_objective

share/github-backup-utils/ghe-prune-snapshots

@@ -24,7 +24,7 @@ prune_snapshot() {
 #if [ ! -f "$GHE_DATA_DIR/in-progress" ] && [ ! -f "$GHE_DATA_DIR/in-progress-restore" ]; then
 # Check for backup or restore in-progress file
 inprogress_file=$(find $GHE_DATA_DIR -maxdepth 1 -type f \( -name "in-progress" -o -name "in-progress-restore" \) -print -quit)
-if [ -z "$inprogress_file" ]; then
+if [[ "$CALLING_SCRIPT" == "ghe-backup" ]]; then
   # First prune all incomplete / failed snapshot directories
   prune_dirs="$(ls -1 "$GHE_DATA_DIR"/[0-9]*/incomplete 2>/dev/null || true)"
   prune_num=$(echo "$prune_dirs" | grep -v '^$' | wc -l)
@@ -43,7 +43,7 @@ if [ -z "$inprogress_file" ]; then
     log_info Pruning $prune_num "expired snapshot(s) ..."
     echo "$prune_dirs" | prune_snapshot
   fi
-else
+elif [ "$CALLING_SCRIPT" != "ghe-backup" ] && [ -n "$inprogress_file" ]; then
   log_info "Detected a running backup/restore process, please wait until that process is complete to prune expired/incomplete snapshots." 1>&2
   log_info "If no such process is running, please remove the "$GHE_DATA_DIR/in-progress*" file and retry again." 1>&2
 fi