---
name: "xpp_sync"
section: "8"
platform: "linux"
package: "dahdi"
version: "1:3.1.0-2.1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/xpp_sync"
---

# xpp\_sync(8)

Handle sync selection of Xorcom Astribanks.

## NAME

xpp\_sync - Handle sync selection of Xorcom Astribanks.

## SYNOPSIS

xpp\_sync \<auto\|dahdi\|nn\>

xpp\_sync \[-v\]

## DESCRIPTION

On a normal operation one Astribank device provides timing for all the other Astribank devices.

When run without parameters, xpp\_sync will display a list of Astribanks (xbuses) that are connected and registered as Dahdi spans. The current xpp sync master will be marked.

If you this an Astribank is connected and yet it does not appear on the output of xpp\_sync, it may be unregistered. Try running dahdi\_registration .

### Parameters

- auto

  Automatically selects the best Astribank for syncing.

- dahdi

  Gets synchronization from the Dahdi sync master.

- nn

  Sets XBUS-*nn* as sync source.

- \-v

  Also print the numeric xpp sync rank.

(Parameter name is case-insensitive)

### Example output:

```
        Setting SYNC
        Current sync: 01
        Best Available Syncers:
         + XBUS-01 (usb-0000:00:10.4-3) [usb:12345678]       [ PRI_TE PRI_NT PRI_TE PRI_NT ]
           XBUS-00 (usb-0000:00:10.4-2) [usb:QA-01]          [ FXS FXO ]
        ==================================================
        WARNING: FXO which is not the syncer cause bad PCM
                 Affected Astribanks are:
        --------------------------------------------------
                XBUS-00
        ==================================================
```

In this example we see that the recommended xpp sync master is XBUS-02 - it is the first on the list. It is also the actual syncer, as we can see from the '+' beside it.

xpp\_sync is normally called from the dahdi init.d script. The parameter it is called with defaults to *auto*, but it is possible to override that parameter (e.g: set it to *dahdi*) through the value of XPP\_SYNC in /etc/dahdi/init.conf .

## FILES

- /sys/bus/astribanks/drivers/xppdrv/sync

  xpp\_sync is essentially a nicer interface to `"/sys/bus/astribanks/drivers/xppdrv/sync"`. That file shows the current xpp sync master.

  Writing to it, force XPP drivers to use a different sync master

## SEE ALSO

**dahdi\_registration**(1), **dahdi\_cfg**(1), README.Astribank