5G Stateful Session Recovery
Required License: 5G Correlation
5G stateful session recovery provides session persistence for GigaSMART 5G applications, including 5G flow filtering, 5G forward listing, and 5G flow sampling. In this method of recovery, 5G sessions are backed up periodically so that they can be recovered faster after a GigaSMART line card reboot or a node reboot.
5G stateful session recovery requires additional memory for storing backups. GigaVUE‑HC3 has the required memory. For GigaVUE‑HC2, Control Card version 2 (HC2 CCv2) is required. Contact your Sales representative or authorized partner for the required control cards for GigaVUE‑HC2.
Using 5G stateful session recovery, the 5G session tables in the GigaSMART line card memory is periodically backed up to the control card memory on the node and stored.
You should configure an interval for how often the backups occur, such as every 10 minutes. If 5G stateful session recovery is enabled and the GigaSMART line card is rebooted, the 5G session tables is restored automatically following the reboot.
The last stored backup file is downloaded from the control card to the GigaSMART line card using FTP. The session table is repopulated from the last stored backup file to each GigaSMART engine, up to 8 engines. Packet count statistics for sessions are saved and restored.
Depending on the size of the session table, the amount of time to restore from the backup might take as much as 3 minutes. During that interval, traffic is blocked to the virtual port on the GigaSMART line card. Once the session table is read and populated, traffic is allowed.
Depending on the interval between backups, there could be differences between the stored state and the current state of the system, for example, map configuration could change, or sessions could be added, modified, or deleted.
Load balancing information is not persisted, so after a session table is repopulated, a session that was once sent to one load balanced port may be sent to a different load balanced port after the reboot. However, for SUPI-based load balancing, the traffic is sent to the same port as it was before the reboot.
5G stateful session recovery works in a cluster environment; however, the cluster leader must remain the same.
Configure 5G Stateful Session Recovery
To enable 5G stateful session recovery, as well as to configure timers, do the following:
| 1. |
On the left navigation pane, click  , and then select Physical>Nodes. |
| 2. | From the device view, select GigaSMART > GigaSMART groups. |
| 3. | Click on the alias of the GigaSMART group. |
| 4. | Select GTP Persistencein the GTP Persistence fields under GigaSMART Parameters as shown in the 1. The timers are pre-configured with default values. |
| 1 | GTP Persistence GigaSMART Parameters |
Use the System widget on the Overview page to determine the amount of memory. The size of memory is 24Gb in an upgraded system.
View Backup and Restore information
To view the System information, select Overview from the Navigation pane. The amount of free and used memory is displayed in the Memory field.
To view backup and restore information for GTP Persistence:
| 1. | Select GigaSMART > GigaSMART Groups > GigaSMART Group. |
| 2. | Click on the alias of the GigaSMART group. |
A Quick View appears for the selected GigaSMART group.
| 3. | Scroll down to GTP Persistence. In 2 GTP Persistence Information, GigaSMART Group gsgrp-1_4_e1 is selected and the Quick View is displayed. |
| 2 | GTP Persistence Information |
The following table describes persistence information.
|
Name |
Format |
|
Backup Info |
|
|
Backup file name |
The internal name of the backup file. |
|
Last successful time |
The time stamp of the last successful backup. |
|
Last fail time |
The time stamp of the last failed backup. |
|
Number of control tunnels |
The number of control tunnels backed up. |
|
Number of user tunnels |
The number of user tunnels backed up. |
|
Number of sessions |
The number of sessions backed up. |
|
Number of success |
The number of successful backups. |
|
Number of failed |
The number of failed backups. |
|
Config Status |
The status of a backup, which is either Enabled or Disabled. |
|
In Progress |
The progress, which is either Yes or No. |
|
Restore Info |
|
|
Last restore time |
The time stamp of the last restore. |
|
Number of tunnels |
The number of tunnels restored. |
|
Number of sessions |
The number of sessions restored. |
Remove Backup files
To delete backup files, do the following:
| 1. | Select the alias of GigaSMART Group. |
| 2. | Click Edit. |
| 3. | Scroll down to GTP Persistence (refer to 4) |
| 4. | Click Delete All under GTP Backup Files. |
| 4 | GTP Backup Files Delete |
