SCSI(Small Computer System Interface)是一套完整的数据传输协议，其主要功能是在主机和存储设备之间传送命令、状态和块数据。
lsscsi输出，[6:0:0:0]分别表示SCSI host:Channel id: Id:Lun；
scsi host为一块基于PCI总线的HBA或者为一个SCSI控制器芯片。每个scsi host可以存在多个channel，一个channel实际扩展了一条SCSI总线。
每个channel可以连接多个scsi节点(对应target)，具体连接的数量与scsi总线带载能力有关，每个scsi节点又包含多个scsi设备(对应lun)
一个scsi Host可能拥有多个channel，每个channel拥有一条scsi总线，每个scsi target可能拥有多个lun，即多个scsi devie。scsi_device就是对lun的抽象
如下是我的系统的lsscsi输出,物理拓扑是HBA<--->expander 背板<--->两个硬盘
xxx@xxx:~$ lsscsi [0:0:0:0] disk ATA INTEL SSDSC2CW24 400i /dev/sda [6:0:0:0] disk ATA SAMSUNG MZ7LH240 B04Q /dev/sdb [6:0:1:0] disk ATA V300 512G-SSDV04 AA20 /dev/sdc [6:0:2:0] enclosu BN BP24D_EA_B341 RevB -
sys文件系统devices下的输出如下
xxx@xxx:~$ ls /sys/bus/scsi/devices/ -l total 0 lrwxrwxrwx 1 root root 0 Jul 26 05:50 0:0:0:0 -> ../../../devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0 lrwxrwxrwx 1 root root 0 Jul 29 02:54 6:0:0:0 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6/port-6:0/expander-6:0/port-6:0:0/end_device-6:0:0/target6:0:0/6:0:0:0 lrwxrwxrwx 1 root root 0 Jul 29 02:54 6:0:1:0 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6/port-6:0/expander-6:0/port-6:0:1/end_device-6:0:1/target6:0:1/6:0:1:0 lrwxrwxrwx 1 root root 0 Jul 29 02:54 6:0:2:0 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6/port-6:0/expander-6:0/port-6:0:36/end_device-6:0:36/target6:0:2/6:0:2:0 lrwxrwxrwx 1 root root 0 Jul 26 05:50 host0 -> ../../../devices/pci0000:00/0000:00:1f.2/ata1/host0 lrwxrwxrwx 1 root root 0 Jul 26 05:50 host1 -> ../../../devices/pci0000:00/0000:00:1f.2/ata2/host1 lrwxrwxrwx 1 root root 0 Jul 26 05:50 host2 -> ../../../devices/pci0000:00/0000:00:1f.2/ata3/host2 lrwxrwxrwx 1 root root 0 Jul 26 05:50 host3 -> ../../../devices/pci0000:00/0000:00:1f.2/ata4/host3 lrwxrwxrwx 1 root root 0 Jul 26 05:50 host4 -> ../../../devices/pci0000:00/0000:00:1f.2/ata5/host4 lrwxrwxrwx 1 root root 0 Jul 26 05:50 host5 -> ../../../devices/pci0000:00/0000:00:1f.2/ata6/host5 lrwxrwxrwx 1 root root 0 Jul 29 02:54 host6 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6 lrwxrwxrwx 1 root root 0 Jul 26 05:50 target0:0:0 -> ../../../devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0 lrwxrwxrwx 1 root root 0 Jul 29 15:59 target6:0:0 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6/port-6:0/expander-6:0/port-6:0:0/end_device-6:0:0/target6:0:0 lrwxrwxrwx 1 root root 0 Jul 29 15:59 target6:0:1 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6/port-6:0/expander-6:0/port-6:0:1/end_device-6:0:1/target6:0:1 lrwxrwxrwx 1 root root 0 Jul 29 15:59 target6:0:2 -> ../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/host6/port-6:0/expander-6:0/port-6:0:36/end_device-6:0:36/target6:0:2 river@inspur:~$
scsi内核log控制开关打开,root用户
echo -1 > /proc/sys/dev/scsi/logging_level
参考
1：Linux Scsi子系统框架介绍(可以知道host target channel id lun的关系）_scsi 通用sg节点名称-CSDN博客
2：Linux命令lsscsi详解 - 一口Linux - 博客园 (cnblogs.com)
标签：00,0000,..,devices,Jul,SCSI,root,lsscsi From： https://www.cnblogs.com/River-blog/p/18376747