HP 5600 Deploying HP KVM consoling solutions best practices - Page 7

Designing a consoling solution Implementation of an efficient multi-server system requires a server management plan. The following functional aspects of server management should be considered: • Number of servers - System size determines the number of switches and adapters required. • Ratio of administrator access paths to servers required - 1 to 4, 1 to 8, or 1 to 16 • Type of access required per server or device to be managed - KVM, serial, local, remote • Access priority - Tiered switches may restrict KVM access to servers due to port blocking. • Virtual media requirements - Whether firmware or software of individual servers needs to be installed or updated remotely • Remote or integrated Lights-Out functionality • Use of legacy console switches and adapters - Expanding an existing system may involve compatibility issues with certain functions. Console switch types, tiering, and port blocking HP offers two basic types of virtual media-enabled KVM console switches: the HP IP Console Switch with Virtual Media and the HP Server Console switch with Virtual Media. Both switch types support 3-level tiering, virtual media support, and a ROM-based OSD interface for local KVM access and control of any directly connected server. The HP IP Console Switch with Virtual Media is recommended as a main access or first tier switch for a management system. It provides both local and remote access. Using IP Console Viewer software and LDAP integration with Active Directory, HP IP Console Switch remote users can fully manage any server connected directly or tiered downstream. The HP Server Console Switch with Virtual Media, on the other hand, enables one or two local KVM users to fully manage any server connected directly or tiered downstream. When tiered downstream from an HP IP Console Switch supporting a remote KVM user, the HP Server Console Switch enables that remote KVM user to access and manage any server connected directly or tiered downstream. In Figure 6, two groups of servers are managed by a local KVM console connected to the first-tier switch. Group A servers are connected directly to the main (first-tier) switch, while group B servers are connected to a second-tier console switch. A third tier can be implemented by connecting one or more switches to the second-tier HP Server Console Switch with Virtual Media. While tiering increases switch capacity, it also introduces port blocking. Each port of a console switch can handle only one active server connection at a time, so mission-critical servers that require priority access by a KVM console should be connected directly to the first (top) tier switch (such as a Group A server in Figure 6). All servers connected through the second tier switch (Group B servers in Figure 6) in effect share a single port of the first tier (main) switch and compete equally for access from the upper tier switch. IMPORTANT While a single KVM console can control up to a theoretical 4,096 servers through three tiers of HP console switches, access requirements and performance issues make such an infrastructure impractical. Performance begins to degrade when the IP Console Viewer database surpasses 1000 objects. Access limitations introduced by port blocking with third-level tiering becomes problematic. 7