call-manager-fallback max-dn

[Gabriel Desroches]

Hello,

I am trying to understand correctly the max-dn function of the Basic SRST mode for IOS 15.5-3-M5

Actually, we would like to have 40 different ephones (max-ephones 40) with 2 DN each registered to the GW (so 80 DN), but each DN would need the possibility to receive more than 2 simultaneous calls.

I am not sure if:

max-dn 80 octo-line

or

max-dn 40 number octo-line

or

max-dn 40 dual-line number octo-line

or

max-dn 80 octo-line number octo-line

would be the appropriate configuration ?

Thank you for your help

[R0g22]

You can just have "max-dn 80" to accommodate the extensions. Dual-line/Octo-line refers to the number of virtual channels/EFXS ports i.e. 2 and 8 respectively which governs how many calls can each DN accommodate. So dual DN's can have 2 simultaneous calls while Octo can have 8.

[Gabriel Desroches]

Thank you for the fast reply.

So, if we want any of the 80 DN to receive up to 8 calls each, it would be:

max-dn 80 octo-line

right ?

If so, then what is the "number" parameter for within' that command ?

Thank you

[R0g22]

That's right. What "number" parameter are you referring to ?

[Gabriel Desroches]

I can't seem to find the document where I read that. The page I looked for a few days ago is now 404 not found, and all other documentations kind of differ. It was a command parameter, similar to "preference". Anyways, it works now, and I can see how the channels are reserved using show voice port summary and show call-manager-fallback ephone-dn

Thank you and have a good day

[R0g22]

Let me know in case you can find the command in here -
https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cusrst/admin/sccp_sip_srst/configuration/guide/SCCP_and_SIP_SRST_Admin_Guide.html

SRST Admin Guide has everything related to traditional SRST and ESRST.

[Gabriel Desroches]

Ok, I found it back, and it is in the admin guide:

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cusrst/admin/sccp_sip_srst/configuration/guide/SCCP_and_SIP_SRST_Admin_Guide/srst_setting_up_using_sccp.html

Search for: number octo-line

But I think I misunderstood it. I guess it only shows that you can set up either directory numbers with dual-line, or octo-line, or both.

So, it could be:

max-dn 10 dual-line

max-dn 10 octo-line

or

max-dn 10 dual-line 10 octo-line

It's just that "number" term that is confusing, it's described as a "parameter" in the purpose section.

Thanks

[R0g22 · Accepted solution]

That's right. It's basically the same thing that I highlighted. The "number" is basically being described as a parameter. So effectively per the doc, they mean -

max-dn <number> dual-line|octo-line

which translates to in the config as -
max-dn 80 dual-line
or,
max-dn 80 octo-line