hosts/pumpkin/backup.nix

   1 { pkgs, lib, hostName, ... }:
   2 with builtins;
   3 {
   4   # Take regular snapshots, and prune old ones
   5   services.sanoid = {
   6     enable = true;
   7     extraArgs = [ "--verbose" ];
   8     datasets = {
   9       "${hostName}/root" = {
  10         autosnap = true;
  11         autoprune = true;
  12         frequently = 0;
  13         hourly = 12;
  14         daily = 7;
  15         monthly = 0;
  16         yearly = 0;
  17         recursive = true;
  18       };
  19       "${hostName}/root/nix" = {
  20         autosnap = false;
  21       };
  22       "${hostName}/root/var/cache" = {
  23         autosnap = false;
  24       };
  25       "${hostName}/root/var/log" = {
  26         autosnap = false;
  27       };
  28       "${hostName}/root/home/julm/.cache" = {
  29         autosnap = false;
  30       };
  31       "${hostName}/root/home/julm/.local" = {
  32         hourly = 0;
  33         daily = 1;
  34       };
  35       "${hostName}/root/home/julm/.mozilla" = {
  36         hourly = 0;
  37         daily = 1;
  38       };
  39       "off2/julm/backup/${hostName}" = {
  40         autosnap = false;
  41         autoprune = true;
  42         hourly = 12;
  43         daily = 14;
  44         monthly = 3;
  45         yearly = 0;
  46       };
  47     };
  48   };
  49   programs.bash.interactiveShellInit = ''
  50     backup-pumpkin () {
  51       local -
  52       set -x
  53       dst=
  54       if ! zpool list off2
  55         then dst=aubergine.sp:
  56         fi
  57       sudo syncoid --sshkey ~julm/.ssh/id_ed25519 \
  58         --create-bookmark --no-sync-snap --no-privilege-elevation \
  59         --preserve-properties --preserve-recordsize \
  60         --recursive --sendoptions=w --recvoptions=u \
  61         --exclude pumpkin/root/nix \
  62         --exclude pumpkin/root/var/cache \
  63         --exclude pumpkin/root/var/log \
  64         --exclude pumpkin/root/home/julm/.cache \
  65         pumpkin/root \
  66         ''${dst}off2/julm/backup/pumpkin
  67       zfs-fix-bookmarks pumpkin 2>/dev/null
  68     }
  69     mount-zfs-backup () {
  70       (
  71       set -eux
  72       zpool="$1"
  73       zpool status "$zpool" 2>/dev/null ||
  74       sudo zpool import -d /dev/disk/by-id/ "$zpool"
  75       trap "sudo zpool export $zpool" EXIT
  76       zfs list -rH -t filesystem -o mounted,mountpoint,name "$zpool"/"$USER"/backup |
  77       grep "^no\\s*/" | cut -f 3 | xargs -ortL1 sudo zfs mount -Olv || true
  78       ${pkgs.mate.caja-with-extensions}/bin/caja --browser /mnt/"$zpool"/"$USER"/backup
  79       )
  80     }
  81   '';
  82   # Trigger backups when disks are plugged
  83   services.udev.extraRules = ''
  84     ACTION=="add",    SUBSYSTEM=="block", KERNEL=="sd*", ENV{ID_SERIAL}=="WDC_WD10JPVT-22A1YT0_WD-WX21AC2F3987", ENV{SYSTEMD_WANTS}+="zfs-local-backup-home@WD10JPVT.service", ENV{SYSTEMD_ALIAS}="/sys/subsystem/usb/WD10JPVT"
  85     # See https://github.com/systemd/systemd/issues/7587#issuecomment-381428545
  86     ACTION=="remove", SUBSYSTEM=="block", KERNEL=="sd*", ENV{ID_SERIAL}=="WDC_WD10JPVT-22A1YT0_WD-WX21AC2F3987", TAG+="systemd"
  87   '';
  88   # Show what's happening to the user
  89   systemd.services."zfs-term@" = {
  90     description = "ZFS terminal for: %I";
  91     unitConfig.StopWhenUnneeded = false;
  92     environment.DISPLAY = ":0";
  93     environment.XAUTHORITY = "/home/julm/.Xauthority";
  94     after = [ "graphical.target" ];
  95     bindsTo = [ "sys-subsystem-usb-%i.device" ];
  96     serviceConfig = {
  97       Type = "simple";
  98       PrivateTmp = true;
  99       ExecStart = pkgs.writeShellScript "zfs-force-import" ''
 100         DESTPOOL=$1
 101         set -eux
 102         ${pkgs.xterm}/bin/xterm -fg white -bg black -fa Monospace -fs 6 \
 103           -title "ZFS backup to: $DESTPOOL" -e "journalctl -f -o short \
 104           -u zfs-force-import@$DESTPOOL \
 105           -u zfs-local-backup-home@$DESTPOOL"
 106       '' + " %I";
 107     };
 108   };
 109   # Force zpool import, even if the disk has not been exported, or has been imported on another computer
 110   systemd.services."zfs-force-import@" = {
 111     description = "ZFS force import: %I";
 112     unitConfig = {
 113       StartLimitBurst = 5;
 114       StartLimitInterval = 200;
 115       StopWhenUnneeded = true;
 116     };
 117     wants = [ "zfs-term@%i.service" ];
 118     bindsTo = [ "sys-subsystem-usb-%i.device" ];
 119     path = lib.mkBefore [ "/run/booted-system/sw" ];
 120     serviceConfig = {
 121       Type = "oneshot";
 122       RemainAfterExit = true;
 123       PrivateTmp = true;
 124       SyslogIdentifier = "zfs-force-import@%i";
 125       Restart = "on-failure";
 126       ExecStart = pkgs.writeShellScript "zfs-force-import" ''
 127         DESTPOOL=$1
 128         set -eux
 129         # Import the zpool, using stable paths
 130         zpool import -d /dev/disk/by-id/ || true
 131         zpool import -lFd /dev/disk/by-id/ "$DESTPOOL" ||
 132         zpool reopen "$DESTPOOL" ||
 133         zpool import -f -d /dev/disk/by-id/ "$DESTPOOL" ||
 134         zpool clear -nFX "$DESTPOOL"
 135       '' + " %I";
 136     };
 137   };
 138   # Prune old snapshots on the backup and send new ones
 139   systemd.services."zfs-local-backup-home@" = {
 140     description = "ZFS backup home, on: %I";
 141     wants = [ "zfs-term@%i.service" ];
 142     after = [ "zfs-force-import@%i.service" ];
 143     requires = [ "zfs-force-import@%i.service" ];
 144     bindsTo = [ "sys-subsystem-usb-%i.device" ];
 145     path = lib.mkBefore [ "/run/booted-system/sw" ];
 146     serviceConfig = rec {
 147       Type = "oneshot";
 148       PrivateTmp = true;
 149       CacheDirectory = [ "zfs-usb-backup/%I" ];
 150       RuntimeDirectory = [ "zfs-usb-backup/%I" ];
 151       User = "julm";
 152       Group = "users";
 153       SyslogIdentifier = "zfs-local-backup-home@%i";
 154       ExecStartPre = "+" + pkgs.writeShellScript "zfs-local-backup-home-startPre" ''
 155         DESTPOOL=$1
 156         set -eux
 157         if zpool status "$DESTPOOL"; then
 158           zfs allow ${User} bookmark,hold,mount,send ${hostName}/home
 159           zfs allow ${User} bookmark,create,destroy,load-key,mount,mountpoint,receive,rollback,snapshot "$DESTPOOL"/${User}
 160           zpool scrub -p "$DESTPOOL" || true
 161         fi
 162       '' + " %I";
 163       ExecStart = pkgs.writeShellScript "zfs-local-backup-home" ''
 164         set -eu
 165         DESTPOOL=$1
 166         # sanoid is quite conservative:
 167         # by setting hourly=24, a snapshot must be >24 hours old
 168         # and there must been >24 total hourly snapshots,
 169         # or nothing is pruned.
 170         install -D -m 400 /dev/stdin /tmp/sanoid/sanoid.conf <<EOF
 171           [template_remote]
 172           autoprune=true
 173           autosnap=false
 174           process_children_only=false
 175
 176           [$DESTPOOL/${User}/backup/${hostName}/home]
 177           hourly=6
 178           daily=31
 179           monthly=3
 180           recursive=true
 181           use_template=remote
 182         EOF
 183         set -x
 184         ${pkgs.sanoid}/bin/sanoid \
 185           --cache-dir /var/cache/zfs-usb-backup/"$DESTPOOL" \
 186           --configdir /tmp/sanoid \
 187           --prune-snapshots \
 188           --run-dir /run/zfs-usb-backup/"$DESTPOOL" \
 189           --verbose
 190
 191         for dataset in ${hostName}/home; do
 192           ${pkgs.sanoid}/bin/syncoid \
 193             --create-bookmark \
 194             --exclude "home/room" \
 195             --force-delete \
 196             --no-privilege-elevation \
 197             --no-sync-snap \
 198             --recursive \
 199             --recvoptions "" \
 200             --sendoptions raw  \
 201             --skip-parent \
 202             "$dataset" \
 203             "$DESTPOOL"/${User}/backup/"$dataset"
 204         done
 205       '' + " %I";
 206       ExecStartPost = "+" + pkgs.writeShellScript "zfs-local-backup-home-startPost" ''
 207         DESTPOOL=$1
 208         set -eux
 209         # Only if the zpool still exists to avoid uninterruptible hanging
 210         if zpool status -v "$DESTPOOL"; then
 211           # Scrub the zpool 1 minute (in the background)
 212           zpool scrub "$DESTPOOL"
 213           sleep 60
 214         fi
 215         while zpool status -v "$DESTPOOL"; do
 216           zpool scrub -p "$DESTPOOL" || true
 217           sleep 20
 218           # Export the zpool (to avoid a forced import later on)
 219           zpool export "$DESTPOOL" || true
 220         done
 221         systemctl --no-block stop zfs-term@"$DESTPOOL"
 222       '' + " %I";
 223     };
 224   };
 225   programs.bash.shellAliases = {
 226     mount-backup-WD10JPVT = "mount-zfs-backup WD10JPVT";
 227   };
 228 }