diff --git a/jobs.nix b/jobs.nix
index 5cd143f..fbf6c20 100644
--- a/jobs.nix
+++ b/jobs.nix
@@ -55,17 +55,12 @@ with lib;
     '';
   };
 
-  system.fsPackages = [ pkgs.nfs-utils ];
-
   systemd.mounts = lib.singleton
     {
-      description = "backup NFS volume";
-      after = [ "network-online.target" ];
-
-      what    = "192.168.1.3:/maxwell";
-      where   = "/mnt/backup";
-      type    = "nfs";
-      options = "nolock";
+      description = "backup volume";
+      what   = "/dev/mapper/backup-maxwell";
+      where  = "/mnt/backup";
+      partOf = [ "backup.service" ];
     };
 
   systemd.services.backup =
@@ -86,8 +81,8 @@ with lib;
 
   in {
     description = "system backup";
-    after       = [ "network-online.target" "mnt-backup.mount" ];
-    bindsTo     = [ "mnt-backup.mount" ];
+    after       = [ "mnt-backup.mount" ];
+    requires    = [ "mnt-backup.mount" ];
     startAt     = "*-*-* 03:00";  # every day at 3:00
     onFailure   = [ "notify-failed@backup.service" ];
 
@@ -109,15 +104,16 @@ with lib;
 
       # build indices and save
       while read -r dir; do
-        name=$(basename "$dir")
+        {
+          name=$(basename "$dir")
+          echo indexing $name...
+          bup index "$dir" --exclude-from="${excluded}"
+          echo done
 
-        echo indexing $name...
-        bup index "$dir" --exclude-from="${excluded}"
-        echo done
-
-        echo saving $name...
-        bup save -n "$name" "$dir"
-        echo done
+          echo saving $name...
+          bup save -n "$name" "$dir" || true
+          echo done
+        } || true
       done < "${saved}"
 
       # postgresql backup
@@ -125,7 +121,7 @@ with lib;
       mkdir -p "$dir"
 
       echo dumping databases...
-      sudo -u postgres pg_dumpall | gzip > "$dir"/db.bak
+      sudo -u postgres pg_dumpall > "$dir"/db.bak
       echo done
 
       echo saving...
@@ -133,6 +129,10 @@ with lib;
       bup save -n postgresql "$dir" --strip-path=/tmp
       echo done
 
+      echo generating par2 files...
+      bup fsck -j 8 -g
+      echo done
+
       # prune backups every week
       if test $(( $(date +%s) / 86400 % 7 )) -eq 0; then
         echo pruning...