Configures automatic VLR failure handling for the SGs service
Exec > Global Configuration > Context Configuration > MME SGs
configure > context
Entering the above command sequence results in the following prompt:
[ no ] vlr-failure duration minutes backoff-timer seconds detach-rate number [ -noconfirm ]
Removes the configuration from this service, which disables automatic
detection and offload of VLRs when an SGs association failure occurs.
Specifies the amount of time in minutes during which all qualifying
UEs will be detached.
The MME splits this duration into
n intervals, 5 seconds apart. For example, a setting of 2
minutes with 100 subscribers would result in the MME processing all subscribers
in the first 2 intervals (10) seconds. Any subscribers remaining at the expiry
of the duration will not be processed.
If no detach rate is defined using the
keyword, a maximum of 50 subscribers are processed per
interval. Any remaining UEs will remain attached until detached by other means
(UE/network detach, etc).
must be an integer from 1 through 3000.
Specifies the period of time the MME will wait following the detection
of a VLR condition before starting the controlled release of affected UEs. The
MME begins offloading UEs following the expiry of this backoff timer. If the
VLR has recovered before the backoff timer expires, no offloading is performed.
must be an integer from 1 to 3000.
This optional keyword specifies a maximum number of detaches to
perform per 5 second cycle.
For example, if 12,000 subscribers are to be detached during a 5
minute window (duration = 5 minutes), the MME calculates 60 cycles (5 minutes /
5-second cycles) which results in 200 UEs to detach per cycle.
If the detach-rate is configured to 100, the MME will only detach 100
per 5 second cycle for, resulting in a total of 6000 detaches. Any remaining
UEs will remain attached until detached by other means (UE/network detach,
must be an integer from 1 to 2000.
This command requires that a valid MME Resiliency license key be
installed. Contact your Cisco Account or Support representative for information
on how to obtain a license.
This command configures the MME to automatically initiate the VLR
offload feature when a SGs association failure is detected.
This command provides equivalent functionality to the
sgs vlr-failure Exec Mode command. The
differences are that the Exec Mode command must be applied manually, while this
Config Mode command is applied automatically when a failure condition is
Both commands cannot be enabled simultaneously. An error message is
reported to the operator if this is attempted.
The following command enables automatic SGs failure handling
functionality. After detecting an SGs association failure, the MME will wait
180 seconds before starting to detach UEs over a 60 minute window, without
exceeding a detachment rate of 100 UEs per 5-second cycle.
vlr-failure duration 60 backoff-timer 180 detach-rate 100