Performing Hitless Software Upgrade on Data Center Devices

1. Navigate to the Infrastructure > Fabrics page in Contrail Command. A list of fabrics is displayed in the Fabrics tab.

2. Click the Upload button in the Images tab. The Upload Image page appears.

3. Enter the required software image details and click Upload. Table 1 lists all the mandatory parameters that must be entered to upload a software image.

   Figure 1: Upload Image

   Table 1: Upload Image Fields

   Field	Description
   Name	Enter a name for the software Image. This name cannot be changed once the image has been uploaded.
   Pick a File	Select the actual image file to be uploaded.
   Vendor name	Enter the image vendor name. For example, Juniper, Arista, and so on.
   Device Family	Enter the device family. For example, junos, junos-qfx, and so on.
   Supported Platforms	Enter all the device platforms that the image is compatible on. For more information on supported platforms, see Contrail Supported Platforms.
   Os Version	Enter the OS version of the image. For example, 18.1R1.10.

   Note:

   In the Os Version field, you should specify an exact OS version of the image. For example, if the OS version is '18.1R1.10 ' then you should specify it as '18.1R1.10' only. If you specify it as '18.1R1', the image upgrade will be successful. However, the upgrade job (running in the backend) will not be able to bring the device out of the maintenance mode (because of version mismatch) with no user feedback.

4. Upon successful image upload, the Images tab appears listing the newly uploaded software image. Apart from the image name, you can edit image details at any time.

   The same list of device images is available for image upgrade in 3.

   Figure 2: Device Images

The list of devices connected in a spine and leaf topology and corresponding details of each device in the selected fabric is displayed. The roles assigned to the devices are also displayed.

You can select one or more devices in the fabric. You can also select multiple images.

Figure 3: Select Device > Assign Devices

The health check parameters confirm that the devices and the network as a whole are stable to perform hitless image upgrade. By default, if health check fails for a particular device, then image upgrade is terminated. You can deselect the Abort on health check failure check box to continue upgrade on a device even if the health check fails.

Figure 4: Select Device > Parameters

The Test Run tab checks that the devices selected for upgrade are not already running the selected software version. The Test Run tab also displays the result of the health check on the devices for the parameters selected previously in the Parameters tab. If health check fails for the selected parameters, then you can go back to the previous page by clicking Previous and either changing the value of the health check parameter or disabling the parameter altogether. You can perform this step multiple times until health check passes for the device or you are able to determine that upgrade on the devices is feasible. Alternatively, you can click Previous and deselect the Abort on health check failure check box in the Parameters tab to continue upgrade on a device even if health check fails.

Figure 5: Testing > Test Run

The leafs are upgraded first and in a separate batch from their corresponding spines. If multihoming is configured on a BMS, the corresponding leafs are upgraded in different batches. No more than half the total number if spines will be upgraded in a batch. The batches are formed so as to have backup devices in a separate batch to the devices being upgraded in order to make the upgrade hitless. You can view the summary of the strategy used to upgrade the devices at the top and you can scroll down to view complete details of the devices. The estimated time for image upgrade per batch is also displayed.

Figure 6: Testing > Strategy Plan

Alternatively, click No to go back to the previous page.

Figure 7: Testing > Strategy Plan Confirmation

Alternatively, to cancel the upgrade process, click Cancel. The Infrastructure > Fabrics page is displayed.