User Manual FAQ Contact Introduction Installation Configuration Scripts Advanced Topics Extensions for SABnzbd

Incorrect or missing information? Switches

This Wiki page is for an older version of SABnzbd.
You can download the most recent stable version (SABnzbd 4.3.2) on our downloads page.


Maximum retries
To prevent deadlock, SABnzbd will only try each server a limited amount of times.
Disconnect on empty queue
Disconnect from Usenet server(s) when queue is empty or paused. This will help you switch between different systems. Set this option off when your server keeps complaining that you have too many connections open.


Pre-queue script
See: pre-queue script.
On queue finish script
Executed after the queue finishes downloading. No special parameters are supplied. For more information on running scripts, read the general information here: pre-queue script.
Propagation delay If you experience very young posts failing due to missing blocks your server might still be in the process of receiving the posts. Delaying the these very young posts a few minutes might solve these issues. Posts will be paused until they are at least this age.
Setting job priority to Force will skip the delay.
Only get articles for top of queue When a top-job stalls for some reason, start downloading segments for the next job. This prevents a job from blocking the queue when you have an unreliable Usenet server. If you need this behavior, set the option off. If you have a reliable server (most paid servers), you might as well set this on.
Check before download

To prevent wasteful downloading, you can let SABnzbd check the presence of a job on the server, before actually downloading it. If less than 100.2% of the total available data (including par2 files) is available, the job will be send to History as failed. When you click "Retry", SABnzbd will attempt the download anyway.

NOTE The check slows down the total download considerably, use only when you're not in a hurry but wish not to waste your quota instead. Also it cannot be completely reliable, due to the way some servers remove posts.

Abort jobs that cannot be completed If on, when during download it becomes clear that it can never be repaired, it will be aborted and send to the History as failed. Should you retry the job, the check will not be done again, but the whole job will be tried instead.
Identical download detection See: Duplicate Detection
Smart duplicate detection See: Duplicate Detection
Allow proper releases
See: Duplicate Detection
Action when encrypted RAR is downloaded For more info see Password-protected RARs. You can choose to either continue, abort or pause the download.
Unwanted extensions

Downloads that contain files with a listed extension can be paused or aborted. Extensions are input as a comma-separated list, for example exe,com,cmd,bat to trigger on common Windows executable content.
Basic wildcards and regular expressions are also supported, for example re:mp* or re:r[0-9]{2} (the latter matching r00 through r99).

In Blacklist mode, only the listed extensions trigger the configured action; everything else is ignored. Whitelist mode is more paranoid: only listed extensions get a free pass; jobs that contain files with any other extension, no matter how small or harmless, will be considered unwanted.

NOTE Whitelist mode is best combined with the Pause action, until you have a carefully curated list of wanted extensions.

Action when unwanted extension detected Pause or abort downloads when an unwanted extension is detected. Setting this option to Off disables detection of unwanted extensions.
Automatically sort queue
Every time a job is added to the queue, the queue can be sorted according to this setting.
NOTE Beware that custom sorting of the queue is lost every time a new job is added.
  • Default = No auto sorting.
  • Sort by % downloaded = Sort jobs by percentage downloaded (re-sorts every 30 seconds).
  • Sort by Age = Sort jobs by their usenet date.
  • Sort by Name = Sort jobs by their Name (not case sensitive).
  • Sort by Size = Sort jobs by their Size/Bytes.
Direct Unpack Jobs will start unpacking during the downloading to reduce post-processing time. Only works for jobs that do not need repair and do not have strongly obfuscated filenames.
This feature is enabled automatically when your disk-speed is greater than 40MB/s. It will not be enabled automatically again if you manual disable it.

Post processing

Pause downloading during post-processing Will pause the queue while verifying and repairing, only needed for resource-constrained systems (like NAS-devices).
Download all par2 files
Download all par2 files when (after verification) the job was damaged. Prevents multiple rounds of verification.
NOTE SABnzbd will already download extra par2 files if it detects problems during the download, so usually this option is not required.
External process priority

Windows-only. Set process priority of programs started by SABnzbd, like the repair and unpack processes.

NOTE Setting High could result in significant slowdown of the system during processing!

Extra PAR2 parameters

Extra arguments that will be passed when running par2 or MultiPar for verification and repair.

Detailed information: Windows and Linux. No extra parameters are available on macOS.

Nice parameters
Linux-only. See Nice to reduce CPU priority.
IONice parameters
Linux-only. See IONice to reduce disk priority.
Enable SFV-based checks
If no par2 files are available, .sfv files (if present) will be used to check files
Post-Process only verified jobs
Even if jobs fail the verification stage, still run unpack and scripts. This way scripts can be notified of a failed download. If turned off, all jobs will be marked as Completed even if they are incomplete.
Enable recursive unpacking
Unpack archives (rar, zip, 7z) within archives.
Ignore any folders inside archives
All files will go into a single folder.
Post-processing script can flag job as failed
Some scripts will return a non-zero exit code when they encounter a problem. You can opt to let a non-zero exit code mark the job as failed. This can be useful when you're using an indexer that offers alternative NZB files or use a front-end (like SickBeard) that will look for alternatives when a job fails.
Ignore samples If enabled, delete anything that looks like sample files (containing the words sample or proof) after completion of post-processing.
Deobfuscate final filenames

If filenames of (large) files in the final folder look obfuscated or meaningless (like 19399393.ext or timmof.mkv) they will be renamed to the job name. Additionally, attempts to set the correct file extension based on the file signature if the extension is not present or meaningless.

NOTE If Sorting is active for a specific job, this feature will not be applied.

Cleanup List List of file (extensions) that should be deleted in the cleanup stage. Examples: .nfo, .nfo, .sfv. You can leave out the dots, so nfo, nzb, sfv will do the same.
History Retention Automatically delete completed jobs from History when new jobs are added or every day at midnight.
  • Keep all jobs = Do not auto-delete any history.
  • Keep maximum number of completed jobs = Specify exact amount of jobs to keep, removing the oldest ones.
  • Keep completed jobs maximum number of days = Delete jobs automatically when they are older than the set amount of days.
  • Do not keep any completed jobs = No jobs are saved in the History.
NOTE Beware that Duplicate Detection and some external tools rely on History information.


Enable folder rename
When SABnzbd does unpacking it will do that in a folder prefixed with _UNPACK_. This is to prevent users or other software from processing the file. Some operating systems cannot handle this. Therefore it's possible to disable the feature.
Replace Spaces in folder name
Enable to replace spaces with underscores in folder names.
Replace underscores in folder name
Enable to replace underscores with dots in folder names.
Replace dots in folder name
Enable to replace dots with spaces in folder names.
Make Windows compatible
Especially useful for servers and sometimes external disks. Make sure names are compatible with Windows.


If you're unlucky enough to have an ISP that uses strict download caps, you may want to set a monthly quota for SABnzb.

Size In bytes. Example: 5G (for 5 GB) or 1T (for 1 TB)
Quota Period Daily, Weekly or Monthly quota
Reset day The day of the week or month when your ISP will reset your cap. Use 31 for the last day of the month. Optionally you can add a time of day, like 23:30.
  • So for monthly you would enter 20 23:30, meaning the 20th of each month at 11:30PM.
  • For weekly 2 4:00, meaning every Tuesday at 4AM.
  • Even daily is possible: 3:00
Auto resume Set this on when you want to resume downloading once the quota has been reset. Otherwise you will have to resume manually

Please note file following:

  • Jobs with Force priority will ignore the paused state.
  • Don't set the quota too high. Leave room for other internet use.

Extra Par2 Parameters for Linux

NOTE For Windows, see below.

You will need to install the multi-core versions of par2 yourself, as described here.

The behavior of multi-core PAR2 can be influenced by an extra parameter. By default it will use all available cores.

  • -t1 Use it single-core
  • -t<n> Use n cores

Extra Par2 Parameters for Windows

The Windows version of SABnzbd has MultiPar integrated which allows you to specify the multi-core behavior and memory usage. Additionally, you can also enable the use of the GPU. Beware: GPU performance varies between systems and can also be slower on some systems.

  • -lc Set this if you want to set number of using threads or want to disable extra feature (SSE2 is always used).

    • -lc<n> where n is from 1 to 11 for specific number of cores
    • -lc12 to use quarter number of physical cores
    • -lc13 to use half of physical cores
    • -lc14 to use 3/4 number of physical cores
    • -lc15 to use the number of physical cores (disable Hyper-Threading)

    You may set additional combinations by adding the following options to the already specified value:

    • +16 to disable SSSE3
    • +128 to disable CLMUL
    • +256 to disable JIT
    • +512 to disable AVX2
    • +32 or +64 (slower device) to enable GPU acceleration

    For example: -lc1 to use single core, -lc32 to enable GPU usage or -lc45 to use half cores and GPU usage.

  • -m Set this if you want to set memory usage. Value is specified from 1 to 7 (1/7th to 7/8th):

    • -m0 = Default (between 6/8 and 7/8 mostly)
    • -m1 = 1/8, 12.5%
    • -m4 = 4/8, 50%
    • -m7 = 7/8, 87.5%

Nice to reduce CPU priority

When SABnzbd runs external tools like par2 and unrar, these tools may use up all CPU capacity. If you set parameters in the nice option box, the tool will be used (if installed). You will need to experiment with the parameters. Leaving the box empty will disable the use of nice.
Popular parameters are -n10.
For more info, see the nice man-page

IONice to reduce disk priority

When SABnzbd runs external tools like par2 and unrar, these tools may use up all disk capacity This can make simultaneous use of the system problematic, e.g. when you want to watch a movie. If you set parameters in the ionice option box, the tool will be used (if installed). You will need to experiment with the parameters. Leaving the box empty will disable the use of ionice.
Popular parameters are -c2 -n4.
For more info, see the ionice man-page

Be careful, using wrong parameters will make all external tools fail!