6.3 Site Upgrade Options

To minimize user interactions, the automated site upgrade makes use of a pair of pre-set options to control certain aspects of the sequence. These options control how many servers remain in service while others are upgrading and are located on the Administration screen under General Options. The default settings for these options maximize the maintenance window usage by upgrading servers in parallel as much as possible.

Figure 6-9 Auto Site Upgrade General Options

The first option that affects the upgrade sequence is the Site Upgrade Bulk Availability setting. This setting determines the number of C-level servers that remain in service during the upgrade. The default setting of 1 equates to 50% availability, meaning a minimum of one-half of the servers stay in service during the upgrade. The default setting is the most aggressive setting for upgrading the site, requiring the minimum number of cycles, thus the least amount of time. The settings of 66% and 75% increase the number of servers that remain in service during the upgrade. Note that increasing the availability percentage may increase the overall length of the upgrade.

A setting of 0 for the bulk availability option allows all of the DPs to be upgraded at once. This setting is not recommended for live production systems.

The Site Upgrade General Options cannot be changed while a site upgrade is in progress. Attempting to change either option while a site upgrade is in progress results in:

[Error Code xxx] - Option cannot be changed because one or more automated site upgrades are in progress

The second option that affects the upgrade sequence is the Site Upgrade SOAM Method. This option determines the sequence in which the SOAMs are upgraded. The default value of 1 considers the OAM HA role of the SOAMs to determine the upgrade order. In this mode, all non-active SOAM servers are upgraded first (in parallel), followed by the active SOAM.

Changing the Site Upgrade SOAM Method setting to 0 causes the standby SOAM and the spare SOAM(s) to be upgraded serially. With this mode, the SOAM upgrade could take as many as four cycles to complete (that is, Spare - Spare - Standby - Active). As for SDS, there are no spare SOAMs, so this setting has no impact on the SOAM upgrade order.

Regardless of the SOAM upgrade method, the active SOAM are always upgraded after the standby SOAM.