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Feedback?This Help article is for Cisco Wireless Phone 9821 registered to Cisco Unified Communications Manager (Unified CM).
The Cisco Wireless Phone 9821 supports Survivable Remote Site Telephony (SRST), ensuring that basic call-processing capabilities remain available during WAN outages. If the phone loses connectivity to its primary, secondary, and tertiary Cisco Unified CM servers, it automatically registers with a local SRST router.
The failover process typically occurs within 10 to 20 seconds if the phone has an active standby connection to an SRST router. Note that total failover time may increase if the device must first attempt connections to secondary or tertiary Cisco Unified CM servers.
Upon restoration of WAN connectivity, the phone automatically attempts to re-register with Cisco Unified CM and deregister from the SRST router, provided it is not currently engaged in an active call.
The following table describes the availability of features during failover.
|
Feature |
Supported |
Notes |
|---|---|---|
|
New Call |
Yes |
|
|
End Call |
Yes |
|
|
Redial |
Yes |
|
|
Answer |
Yes |
|
|
Hold |
Yes |
|
|
Resume |
Yes |
|
|
Conference |
Yes |
|
|
Conference to Active Calls (Join) |
No |
The Active Calls softkey doesn’t display. |
|
Conference List |
No |
|
|
Transfer |
Yes |
|
|
Transfer to Active Calls (Direct Transfer) |
No |
|
|
Auto Answer |
Yes |
|
|
Call Waiting |
Yes |
|
|
Caller ID |
Yes |
|
|
Audible Message Waiting Indicator |
No |
|
|
Unified Session Presentation |
Yes |
Conference is the only feature supported due to other feature limitations. |
|
Voicemail |
No |
Voicemail won’t be synchronized with other users in the Cisco Unified Communications Manager cluster. |
|
Call Forward All |
Yes |
Forward state is only available on the phone that sets the forward because there are no shared line appearances in SRST mode. The Call Forward All settings aren’t preserved on failover to SRST from the Cisco Unified Communications Manager, or from SRST fail-back to the Communications Manager. Any original Call Forward All still active on the Communications Manager should be indicated when the device reconnects to the Communications Manager after failover. |
|
Speed Dial |
Yes |
|
|
To Voicemail (iDivert) |
No |
The iDivert softkey doesn’t display. |
|
Park Monitoring |
No |
The Park softkey doesn’t display. |
|
Barge |
No |
The Barge softkey doesn’t display. |
|
Enhanced Message Waiting Indication |
No |
Message count badges don’t appear on the phone screen. Only the Message Waiting icon displays. |
|
Directed Call Park |
No |
The softkey doesn’t display. |
|
BLF |
No |
BLF feature key works like Speed Dial keys. |
|
Hold Reversion |
No |
Calls remain on hold indefinitely. |
|
Remote Hold |
No |
Calls appear as Local Hold calls. |
|
Meet Me |
No |
The Meet Me softkey doesn’t display. |
|
PickUp |
No |
The softkey causes no action. |
|
Group PickUp |
No |
The softkey causes no action. |
|
Other PickUp |
No |
The softkey causes no action. |
|
Malicious Call ID |
No |
The softkey causes no action. |
|
QRT |
No |
The softkey causes no action. |
|
Hunt Group |
No |
The softkey causes no action. |
|
Intercom |
No |
The softkey causes no action. |
|
Mobility |
No |
The softkey causes no action. |
|
Privacy |
No |
The softkey causes no action. |
|
Call Back |
No |
The Call Back softkey doesn’t display. |
|
Shared Line |
No |
|
|
Service URL |
Yes |
The programmable line key with a Service URL assigned is displayed. |
For more information about supported firmware and Survivable Remote Site Telephony, see Cisco Unified Survivable Remote Site Telephony Compatibility Information.
Set up SRST for Cisco Wireless Phone 9821
You can set up SRST for Cisco Wireless Phone 9821 so that basic call-processing capabilities remain available during WAN outages.
Before you begin
You have a device pool with SRST Reference specified.
| 1 |
In Cisco Unified Communications Manager Administration, select . |
| 2 |
Locate the phone that you will set up. |
| 3 |
Navigate to the Device Information pane, and then select the device pool with SRST reference in the Device Pool field. |
| 4 |
Select Save. |
| 5 |
Select Apply Config. |
| 6 |
(Optional) Repeat step 1 to step 5 on the secondary and tertiary Cisco Unified CM servers. |
