This article summarizes the knowledge of hp xp series storage. the operating system platform is hp_ux11.11.1. disk sharding policy the XP series stores four physical hard disks as one group. divide eight groups of physical hard disks into one Cu. then, according to the customer's requirements, each group of disks is divided into multiple ldev (here, each ldev is the PV that the operating system can recognize. that is, the operating system regards each ldev in the storage as a physical hard disk .) the size of each ldev is determined by the customer according to open-n. (Open-K is 1.88g, open-3 is 2.461g, open-8 is 7.347g, open-E is 14.582g, and open-L, open-V, etc) 2. the meaning of cxtydz in XP series storage. CX represents the channel. that is, the channel from which the device arrived at the system. here, X is the number allocated by the operating system for the optical fiber card. when the same device performs channel redundancy (such as auto path), it will be identified as different devices by the system. their Y and Z numbers are the same, but X is different. because they are the same device, but the two channels are recognized by the system. tydz indicates the specific device. t represents the SCSI device, and y can be any number from 0 to 15. d indicates the device under T. Z can be any number from 0 to 7. that is to say, D is a more detailed description of the T device and a further subdivision of the T device. for example, if T represents a SCSI Storage, D can be one of the hard disks. if t represents a SCSI library, D can be one of them. it should be noted that in the XP series storage, txdz is not defined by the operating system, and T and D are not the meaning mentioned above. here, after dividing XP into multiple Cus: ldev, each Cu: ldev is assigned a unique txdz number by certain algorithms in the XP system. therefore, txdz is not the original meaning. in order to cater to the Recognition Methods of the operating system, XP uses the corresponding Cu: ldev. (In XP, Cu: ldev has read the txdz code table, but I cannot find the document now. I will post it later .) 3. for other concepts, enter the xpinfo-I command in the operating system. Several concepts are displayed in the result, which are described as follows: (1) Device File: Each ldev device file in the operating system. there's nothing to say. (2) Alpa represents a hardware. the number is the logical address assigned by the optical fiber switch to the optical fiber port on XP. if the number is the same, it indicates that the disk is from the same optical fiber port. (This number may not be accurate because it is assigned by the switch .) normally, it corresponds to the following port numbers one by one, or not one by one. it doesn't matter. port refers to the IP address allocated by XP to its optical fiber port. the address of each optical fiber port is unique. therefore, this port address can accurately describe the attributes of the optical fiber port. (3) Lun is a logical UNIX number, logical unit number. lun is the minimum unit used to describe external storage. here, it represents ldev. (I think. not necessarily true .) (4) Serial is a number allocated by XP for each ldev. you don't have to know what's going on. it cannot be used.
In multiple XP environments, the serial items in xpinfo can be used to distinguish the XP on which the Lun is located.
