ChanIsAvail()

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Check channel availability

Last reviewed 2026-04-14

ChanIsAvail([Technology/Resource,options])
Dialplan Builder -- build your ChanIsAvail() command
Specification of the device(s) to check. These must be in the format of `Technology/Resource`, where *Technology* represents a particular channel driver, and *Resource* represents a resource available to that particular channel driver.
Check for all available channels, not only the first one
Consider the channel unavailable if the channel is in use at all
Simply checks if specified channels exist in the channel list
Full arguments reference
  • Technology/Resource
    • Technology/Resource required - Specification of the device(s) to check. These must be in the format of Technology/Resource, where Technology represents a particular channel driver, and Resource represents a resource available to that particular channel driver.
    • Technology2/Resource2 - Optional extra devices to check (multiple)
  • options
    • a - Check for all available channels, not only the first one
    • s - Consider the channel unavailable if the channel is in use at all
    • t - Simply checks if specified channels exist in the channel list
Description

This application will check to see if any of the specified channels are available.

This application sets the following channel variables:

  • AVAILCHAN - The name of the available channel, if one exists
  • AVAILORIGCHAN - The canonical channel name that was used to create the channel
  • AVAILSTATUS - The device state for the device
  • AVAILCAUSECODE - The cause code returned when requesting the channel
Arguments
  • Technology/Resource
    • Technology/Resource required - Specification of the device(s) to check. These must be in the format of Technology/Resource, where Technology represents a particular channel driver, and Resource represents a resource available to that particular channel driver.
    • Technology2/Resource2 - Optional extra devices to check (multiple)
  • options
    • a - Check for all available channels, not only the first one
    • s - Consider the channel unavailable if the channel is in use at all
    • t - Simply checks if specified channels exist in the channel list
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