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Egenera is frequently asked to compare our PAN Manager Software to Cisco’s Unified Computing System (UCS).   Conceptually the two products are similar in that they are based on the concept of stateless servers with virtual I/O and fully converged networking. But PAN Manager has been around for 10 years… so we’ve had a long time (and lots of customer input) to help mature the product and increase its simplicity. So once in a while, the contrast between the two products is so great, that we just have to highlight it. Here’s an example: With Cisco, there are a number of SAN configuration and troubleshooting steps to go through. We’ve compared them to the much more simple/elegant approach that PAN Manager has taken. The following comparison is directly excerpted from Cisco’s UCS Troubleshooting Guide, Chapter 6. We’ll let the items speak for themselves, and emphasize that PAN Manager’s out-of-the-box SAN Boot experience is significantly simpler and less error prone... which results in a better user experience. Cisco SAN Connectivity Checklist - Excerpted from Cisco’s UCS SAN Boot Checklist

• Are the Fibre Channel uplink ports configured in Cisco UCS Manager? >> PAN Manager does not require configuring Fibre Channel uplinks for storage; it automatically discovers disks allocated to it and provides a simple list for the administrator to pick from.

• Do the numbers assigned to the Virtual Storage Area Networks (VSANs) in Cisco UCS Manager match those configured in the Fibre Channel switch? >>PAN Manager does not require or represent the concept of a fiber channel switch (and its setting).  The administrator simply allocates the set of disks for a given server by picking from a list.

• Is N-Port ID Virtualization (NPIV) enabled on the Fibre Channel switch? >> PAN Manager does not have any special requirements for the Fibre Channel switch. It will work with any Fibre Channel switch.

• Is the Cisco UCS fabric interconnect logged into the Fibre Channel switch? The Fibre Channel switch displays the fabric interconnect as an NPIV device. For example, you can use the show fcns data command on a Multilayer Director Switch (MDS). >> The administrator for a PAN System never has to login to the Fibre Channel switch to determine if a server is logged in. PAN Manager automatically connects to the Fiber Channel network at startup time, but not for the boot of each server.

• Is the World Wide Name (WWN) in the correct format in Cisco UCS Manager? >> The administrator in a PAN system does not need to manage WWNs for individual servers. Instead, disks are zoned to small set of WWNs for the PAN system and then the administrator uses PAN Manager to allocate disks directly to each server.

• Have you upgraded the server adapters to use the latest firmware? >> PAN Manager automatically configures Blades to insure 100% successful SAN boot.

• Have you verified the SAN boot and SAN boot target configuration in the boot policy included with the service profile associated with the server? >> PAN Manager does not require any special configuration to establish the boot target. PAN Manager simply boots from the first disk allocated to a server.

• Do the vNIC and vHBA names in the boot policy match those in the vHBA assigned to the service profile? >> PAN Manager does not require matching vHBA names for booting. Instead, the administrator simply allocates the boot disk as the first disk and then boots the server.

• Is the array Active/Passive? >> In a PAN system, the server is completely insulated from the storage array architecture. So, you never need to ask a question like this.

• Are you booting to the active controller on the array? >> In PAN Manager, the server is completely insulated from the storage array architecture.

Cisco SAN Array Configuration Checklist

• Has the host been acknowledged or registered by the array? >> This is never an issue for a PAN system. PAN Manager automatically connects to the Fiber Channel network at startup time and not for the boot of each server.

• Is the array configured to allow the host to access the Logical Unit Number (LUN)? For example, is LUN security or LUN masking configured? >> In a PAN system, you never have to debug disk connectivity issues for a given server. If the disk is seen by PAN Manager, then you are guaranteed that the server will have access to it.
• Did you correctly configure the LUN allocation with the World Wide Port Name (WWPN) assigned in the Cisco UCS instance? If you assign and configure with a World Wide Node Name (WWNN), you could encounter issues. >> This is never an issue in a PAN system for a server. As mentioned above, the administrator allocates a disk to a server by simply selecting from the PAN Manager’s list of disks. There are no per server WWNs to manage.
• Did you map the backed LUN of the array to the same LUN number configured in the Cisco UCS boot policy? >> The administrator in a PAN system does not have to keep track of this kind of mapping. PAN Manager simply boots from first disk associated with the server.