When an upgrade is required on 21 Security Gateways managed by a single Security Management...

The correct answer isD. Central Deployment in SmartConsole is the recommended method for deploying Hotfixes, Jumbo Hotfix Accumulators, and upgrade packages to multiple Security Gateways and Cluster Members. The R82 Security Management Administration Guide states that administrators can select up to30 Security Gateways and Cluster Members, but installation can take place on only10 targets at the same time; targets above the tenth are placed in a queue and processed as earlier installations complete. This directly matches the scenario with 21 Security Gateways. Option A is wrong because the concurrency limit is not one target at a time. Option B is wrong because the administrator is not limited to selecting only 10 targets; the selection limit is higher, while the simultaneous installation limit is 10. Option C is flatly incorrect because Central Deployment is specifically designed for batch deployment from SmartConsole. For CCSE R82, memorize the operational rule:select up to 30, install on up to 10 concurrently, queue the rest. Reference topic:Central Deployment of Hotfixes and Version Upgrades.

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