SCSI 接口具有应用范围广, 多任务, 带宽大, CPU 占用率低, 以及热插拔等优点, 在服务器中广泛的应用.
当然在虚拟化平台支持下, 也能模拟出 SCSI 设备, 方便在虚拟机上热添加 SCSI 设备(一般是硬盘)
但是在热添加 SCSI 设备之后, 需要手动 rescan SCSI 设备.
比较常见的做法是输入如下命令
echo "- - -"> /sys/class/scsi_host/host*/scan
CentOS/RHEL5.9 开始 (SUSE11/12 也有这个工具) 提供一个工具包 sg3_utils 同样可以方便的实现 rescan 操作
- # yum install sg3_utils
- # /usr/bin/rescan-scsi-bus.sh
即可 rescan SCSI 设备
以下是 rescan-scsi-bus.sh 的说明
- # /usr/bin/rescan-scsi-bus.sh --help
- Usage: rescan-scsi-bus.sh [options] [host [host ...]]
- Options:
- -a scan all targets, not just currently existing [default: disabled]
- -d enable debug [default: 0]
- -l activates scanning for LUNs 0--7 [default: 0]
- -L NUM activates scanning for LUNs 0--NUM [default: 0]
- -w scan for target device IDs 0--15 [default: 0--7]
- -c enables scanning of channels 0 1 [default: 0 / all detected ones]
- -m update multipath devices [default: disabled]
- -r enables removing of devices [default: disabled]
- -f flush failed multipath devices [default: disabled]
- -i issue a FibreChannel LIP reset [default: disabled]
-u look for existing disks that have been remapped
-s look for resized disks and reload associated multipath devices, if applicable
- --alltargets: same as -a
- --remove: same as -r
- --flush: same as -f
- --issue-lip: same as -i
- --wide: same as -w
- --multipath: same as -m
- --forceremove: Remove stale devices (DANGEROUS)
- --forcerescan: Remove and readd existing devices (DANGEROUS)
- --nooptscan: don't stop looking for LUNs if 0 is not found
- --color: use coloured prefixes OLD/NEW/DEL
- --hosts=LIST: Scan only host(s) in LIST
- --channels=LIST: Scan only channel(s) in LIST
- --ids=LIST: Scan only target ID(s) in LIST
- --luns=LIST: Scan only lun(s) in LIST
- --sync/nosync: Issue a sync / no sync [default: sync if remove]
- --attachpq3: Tell kernel to attach sg to LUN 0 that reports PQ=3
- --reportlun2: Tell kernel to try REPORT_LUN even on SCSI2 devices
- --largelun: Tell kernel to support LUNs> 7 even on SCSI2 devs
- --sparselun: Tell kernel to support sparse LUN numbering
- --update: same as -u
- --resize: same as -s
Host numbers may thus be specified either directly on cmd line (deprecated) or
or with the --hosts=LIST parameter (recommended).
- LIST: A[-B][,C[-D]]... is a comma separated list of single values and ranges
- (No spaces allowed.)
本文参考链接如下
How do I rescan an HP Smart Array for new devices without rebooting? https://access.redhat.com/solutions/7832
How to rescan the SCSI bus to add or remove a SCSI device without rebooting the computer https://access.redhat.com/solutions/3941
- ADDING/REMOVING A LOGICAL UNIT THROUGH RESCAN-SCSI-BUS.SH https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/storage_administration_guide/logical-unit-add-remove
- HOWTO: Add, Resize and Remove LUN without restarting SLES or OES Linux https://www.suse.com/support/kb/doc/?id=7009660
来源: http://www.bubuko.com/infodetail-2563469.html