# LTO Backup Scripts Scripts to help me perform my backups to Ultrium LTO tapes. ## Movies Library * `mkbak_media.sh`: Incremental subdirectory backup. Take each directory in my cwd, tar it, and append it to tape, one tape entry per directory. Create / extend a CSV index denoting when and to what tape ID the backup was made. Do not backup directories that were already backed up to other media (using the index). Note: Changes in directories will not be detected. The directory name is the only clue. # LTO Notes ## General stuff * dev/nst does not auto-rewind, dev/st does * use mt-st seek / tell to position the tape at block indexes * Remaining capacity: https://serverfault.com/questions/853302/determine-remaining-capacity-of-lto-tape * `sg_logs -a $DEV | sed -n 's/\s*Main partition remaining capacity (in MiB):\s*\(.*\)/\1/p'` * Disable compression: `mt-st -f /dev/nst0 compression 0` * Make seek/tell work: `mt-st -f /dev/nst0 stsetoptions scsi2logical` ## Improve start/stop If you have a slow source / destination, consider using mbuffer with a size of a couple of Gigs. But that might also break speed matching, causing start / stop rather than going slower... idk. ## Backups ### Encrypted tar using GPG `tar cvO --exclude dir/excludeme dir/ | gpg --encrypt --sign --default-key KEY-ID -r KEY-ID -z 0 dd of=/dev/nst0 bs=512k` To decrypt, simply use `gpg --decrypt /dev/nst0` # LTFS on LTO-6 My drives are a little weird, to get it to work I need to edit LTFS sources. `ltfs-2.4.3.1-10461/src/tape_drivers/linux/sg/sg_tape.c`: Type is incorrectly auto detected, we need to always `/* Use LogPage 0x31 */` See this patch for inspiration ``` diff --git a/src/tape_drivers/linux/sg/sg_tape.c b/src/tape_drivers/linux/sg/sg_tape.c index f583079..1169e44 100644 --- a/src/tape_drivers/linux/sg/sg_tape.c +++ b/src/tape_drivers/linux/sg/sg_tape.c @@ -513,6 +513,12 @@ static int _raw_open(struct sg_data *priv) return -EDEV_DEVICE_UNSUPPORTABLE; /* Unsupported device */ } + /* Special care about Quantum model B */ + if (priv->vendor == VENDOR_QUANTUM) { + if (id_data.product_id[7] == ' ') + priv->vendor = VENDOR_QUANTUM_B; + } + if (priv->drive_serial[0]) { /* if serial number is already set, compare it */ if (strcmp(priv->drive_serial, id_data.unit_serial)) { @@ -2969,7 +2975,8 @@ int sg_remaining_capacity(void *device, struct tc_remaining_cap *cap) memset(buffer, 0, LOGSENSEPAGE); if ((IS_LTO(priv->drive_type) && (DRIVE_GEN(priv->drive_type) == 0x05)) || - (priv->vendor == VENDOR_HP && IS_LTO(priv->drive_type) && (DRIVE_GEN(priv->drive_type) == 0x06))) { + (priv->vendor == VENDOR_HP && IS_LTO(priv->drive_type) && (DRIVE_GEN(priv->drive_type) == 0x06)) || + (priv->vendor == VENDOR_QUANTUM_B && IS_LTO(priv->drive_type))) { /* Use LogPage 0x31 */ ret = sg_logsense(device, (uint8_t)LOG_TAPECAPACITY, (uint8_t)0, (void *)buffer, LOGSENSEPAGE); diff --git a/src/tape_drivers/tape_drivers.h b/src/tape_drivers/tape_drivers.h index a9d7bf5..6e11771 100644 --- a/src/tape_drivers/tape_drivers.h +++ b/src/tape_drivers/tape_drivers.h @@ -178,6 +178,7 @@ enum { VENDOR_IBM, VENDOR_HP, VENDOR_QUANTUM, + VENDOR_QUANTUM_B, }; enum { ```