There are three different kind of groups in Asterisk:
(1) group=blah— This is used to bundle (typically trunk) interfaces together so that you can use something like Dial,Zap/g2/…. to use any of the channels in group 2.
(2) callgroup=blah— This is a list of group memberships that you belong to for call pickup purposes
(3) pickupgroup=blah— This is a list of groups that you are permitted to pickup in.
For #2 and #3, basically, you just dial *8# and you can pickup a ringing phone if you have a group in your pickupgroup that is in their callgroup.
hint: pickupgroup is for FXS interfaces while callgroup is for FXO interfaces.
group has nothing to do with either callgroup or pickupgroup.
callgroup is a group of incoming “calls”.
pickupgroup is for membership purposes.
A channel that belongs to a pickupgroup, can pickup all incoming calls on the same callgroup by hitting *8#.
A channel can belong to multiple pickupgroup‘s, ie:
pickupgroup=1,2,3This channel would then be able to pickup calls on callgroup 1, 2 or 3 by hitting *8#.
You can change *8 to something else – see Asterisk config features.conf
group =sets the group membership for all channels beneath where you define it.
group =can be a single group or a list of groups.
For example:
group = 1
channel => 1-4
group = 1,2
channel => 5-6
group = 2,3
channel => 7-8
group = 4
channel => 9-12
group =
channel => 13-16
- Channnels 1-4 are in just group 1.
- Channels 5 and 6 are in groups 1 and 2.
- Channels 7 and 8 are in groups 2 and 3.
- Channels 9-12 are in group 4, and
- Channels 13-16 are in no groups… so…
1,1,Dial,Zap/g1...would give you the first channel in the range 1-6 that was available.
1,1,Dial,Zap/G1...would give you the largest channel in the range 1-6 that was available ((see https://www.voip-info.org/asterisk-zap-channels/)).
1,1,Dial,Zap/g2...would give you the first channel in the range 5-8 that was available.
1,1,Dial,Zap/g3...would give you the first channel in the range 7-8 that was available
1,1,Dial,Zap/g4...would give you the first channel in the range 9-12 that was available.
Note that the pickupgroup and callgroup use the same semantics but have to do with remote call pickup.
April 7, 2023
Phone System 