Storage LUN Problems

How many Luns are stored? 1. How does one identify Luns in Linux? (Is AIX similar?) after a LUN is created and a storage group is created, can the host (linux) Identify the LUN using fdisk-l directly, or must it be restarted? (Note: I have not tried the real machine, so I have to post a question) 2. How can I identify the host after the LUN is resized? However, after the LUN capacity of the storage pool is expanded, what operations are required for windows, linux, and AIX hosts to identify the LUN size after expansion? 3. after a storage group is created, must the host agent be installed on the host to identify the LUN, or what are the advantages of installing the host agent? Linux provides many methods to scan the SCSI bus and identify SCSI devices. Before the 2.4 kernel, dynamic scanning is not supported, and I/O is interrupted until the 2.6 kernel supports dynamic scanning, however, the kernel does not provide commands to dynamically reconfigure SCSI devices, such as HPUX ioscan. Therefore, the only method is: ◆ restart OS ◆ re-load the HBA driver and use the modprobe ◆ 2.4 kernel configuration/proc tool, for example: # echo "scsi add-single-device 0 1 2 3">/proc/scsi ◆ 2.6 kernel run/sys scan, for example: # cd/sys/class/scsi_host/host1/# ls-al scan # echo '---'> scan ◆ execute scan using scripts from HBA vendors, such as QLogic #. /ql-dynamic-tgt-lun-disc.sh -- scanEmulex # lun_scan all ◆ use the Linux publisher script to execute scan, for example: SLES #/bin/rescan-scsi-bus.sh-h 1. after the LUN is divided into a host, the linux host does not need to perform any operations. After a while, you can use fdisk-l to discover the LUN. 2. After LUN resizing, windows needs to use diskpart to expand, diskpart> select volume> extend. In linux, resize2fs is used for online resizing. However, I did not find the two mentioned in the article: 1. To expand the LUN on the AIX host, you must uninstall the volume first, and there is no other method. 2. Before you expand a LUN or create a metaLUN in a RAID group, you must understand whether the host operating system can recognize the LUN without reformat. The following lists the operating systems that can use extended RAID groups and volumes on the CLARIION Storage System: aix jfs-with Logical Volume Manager (LVM) HP-UX JFS-with LVMLinux EXT2-with LVMSolaris UFS-with the embedded Volume Manager and vxresizeSolaris VxFS-with the embedded Volume Manager and vxresizeWindows 2000 Windows 2003-NTFS with Basic and Dynamic Disk LUN ExpansionWindows NT NTFS-you need to restart NetWare nssirix xfs-with XLV Volume Manager when you expand the RAID group/LUN, be sure Use the correct operating system guide and follow the correct operation steps. When the user initially crashes Any RAID group/LUN expansion process, make sure that the user has backed up the file system LInux and used LVM to manage logical volume expansion. Step 1: Add a disk and enter the system. Run fdisk. This command is used to format new disk partitions, for example,/dev/sdb1; 2: Create pv: pvcreate/dev/sdb13: Extended VG: vgextend/dev/VolGroup00/dev/sdb14: Run vgdisplay to view the expanded VG. If the displayed capacity increases, the VG is expanded successfully. 5: Expand LV: lvextend-L + n (M, or G)/dev/VolGroup00/LogVol00/dev/VolGroup00 restart the machine, enter Resuce mode, and select skipp when loading the disk. 6. Activate VG: Run lvm vgchange-a y/dev/VolGgroup007: Run e2fsck to check the file system. E2fsck/dev/VolGroup00/LogVol008: resize2fs/dev/VolGroup00/LogVol00 as long as the lvextend command of LVM is used, it must support online logical volume scaling without affecting applications. However, this is not the same as the online extension file system, and the file system must support online extension. HPUX's JFS and AIX's JFS are completely two things. HPUX's JFS is the product of its OEM of Veritas's VxFS. The strange thing is that it is because it is based on earlier versions of VxFS and does not support online expansion. When this becomes a serious problem, it has been pushed to the market for a long time. Later, in order to solve this problem, hpux oem the online JFS that supports online expansion. However, it requires additional purchase and installation. Is extendfs. The JFS of AIX is completely IBM's own. Currently, JFS is the second generation by default and can be directly used for online expansion. ORACLE's ASM uses logical volumes as bare devices and completely skips the file system.