/sys/class/ scsi _host中有太多scsi主机。只使用一个SCSI控制器，另两个不使用

Question

我的虚拟堡垒服务器中有8个磁盘，这里还共享PCI地址以及控制它们的主机ID。然而，lspci列出了三个驱动器控制器。这是否意味着其他两个根本不使用，这里只使用SCSI Controller: LSI Logic。如果只使用host0 and other hosts，为什么要使用host2。

[root@linux_server ~]# fdisk -l | grep -i disk |grep -v identifer | grep -v identifier | grep -v mapper

Disk /dev/sda: 46.2 GB, 46170898432 bytes
Disk /dev/sdb: 8589 MB, 8589934592 bytes
Disk /dev/sdd: 21.5 GB, 21474836480 bytes
Disk /dev/sde: 53.7 GB, 53687091200 bytes
Disk /dev/sdc: 10.7 GB, 10737418240 bytes
Disk /dev/sdf: 8589 MB, 8589934592 bytes
Disk /dev/sdg: 2147 MB, 2147483648 bytes
Disk /dev/sdh: 2147 MB, 2147483648 bytes

[root@linux_server ~]# ls -l /sys/block/sd*

lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sda -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:0/2:0:0:0/block/sda
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sdb -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:1/2:0:1:0/block/sdb
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sdc -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:2/2:0:2:0/block/sdc
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sdd -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:3/2:0:3:0/block/sdd
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sde -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:4/2:0:4:0/block/sde
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sdf -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:5/2:0:5:0/block/sdf
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sdg -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:6/2:0:6:0/block/sdg
lrwxrwxrwx 1 root root 0 Sep  2 06:39 /sys/block/sdh -> ../devices/pci0000:00/0000:00:10.0/host2/target2:0:8/2:0:8:0/block/sdh

[root@linux_server ~]# lspci | egrep -i "sata|scsi|ide"

00:07.1 IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)
00:10.0 SCSI storage controller: LSI Logic / Symbios Logic 53c1030 PCI-X Fusion-MPT Dual Ultra320 SCSI (rev 01)
02:04.0 SATA controller: VMware SATA AHCI controller

[root@linux_server ~]# cat /sys/class/scsi_host/host*/proc_name | wc -l

33

[root@linux_server ~]# ls -l /sys/class/scsi_host/host*

lrwxrwxrwx 1 root root 0 Sep  2 06:24 /sys/class/scsi_host/host0 -> ../../devices/pci0000:00/0000:00:07.1/host0/scsi_host/host0
lrwxrwxrwx 1 root root 0 Sep  2 06:24 /sys/class/scsi_host/host1 -> ../../devices/pci0000:00/0000:00:07.1/host1/scsi_host/host1
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host10 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host10/scsi_host/host10
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host11 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host11/scsi_host/host11
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host12 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host12/scsi_host/host12
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host13 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host13/scsi_host/host13
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host14 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host14/scsi_host/host14
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host15 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host15/scsi_host/host15
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host16 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host16/scsi_host/host16
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host17 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host17/scsi_host/host17
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host18 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host18/scsi_host/host18
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host19 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host19/scsi_host/host19
lrwxrwxrwx 1 root root 0 Sep  2 06:24 /sys/class/scsi_host/host2 -> ../../devices/pci0000:00/0000:00:10.0/host2/scsi_host/host2
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host20 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host20/scsi_host/host20
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host21 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host21/scsi_host/host21
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host22 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host22/scsi_host/host22
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host23 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host23/scsi_host/host23
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host24 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host24/scsi_host/host24
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host25 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host25/scsi_host/host25
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host26 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host26/scsi_host/host26
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host27 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host27/scsi_host/host27
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host28 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host28/scsi_host/host28
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host29 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host29/scsi_host/host29
lrwxrwxrwx 1 root root 0 Sep  2 06:24 /sys/class/scsi_host/host3 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host3/scsi_host/host3
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host30 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host30/scsi_host/host30
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host31 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host31/scsi_host/host31
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host32 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host32/scsi_host/host32
lrwxrwxrwx 1 root root 0 Sep  2 06:24 /sys/class/scsi_host/host4 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host4/scsi_host/host4
lrwxrwxrwx 1 root root 0 Sep  2 06:24 /sys/class/scsi_host/host5 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host5/scsi_host/host5
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host6 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host6/scsi_host/host6
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host7 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host7/scsi_host/host7
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host8 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host8/scsi_host/host8
lrwxrwxrwx 1 root root 0 Sep  2 06:27 /sys/class/scsi_host/host9 -> ../../devices/pci0000:00/0000:00:11.0/0000:02:04.0/host9/scsi_host/host9

[root@linux_server ~]# for i in `ls /sys/class/scsi_host/`; do echo $i; cat /sys/class/scsi_host/$i/proc_name| grep -i mpt; done

host0
host1
host10
host11
host12
host13
host14
host15
host16
host17
host18
host19
host2
mptspi
host20
host21
host22
host23
host24
host25
host26
host27
host28
host29
host3
host30
host31
host32
host4
host5
host6
host7
host8
host9

Answer 1

host0和host1是从这里来的：

00:07.1 IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)

它支持VMware虚拟CD/DVD仿真。该控制器的物理版本有两个IDE通道，如果我没记错的话，VMware允许同时使用最多两个虚拟CD。

您的实际/dev/sd*磁盘设备目前似乎是通过host2运行的，这是一个：

 00:10.0 SCSI storage controller: LSI Logic / Symbios Logic 53c1030 PCI-X Fusion-MPT Dual Ultra320 SCSI (rev 01)

这是VMware仿真一个简单的并行SCSI控制器，以达到最大的兼容性。

host3 . host32与VMware SATA AHCI controller相关，D8似乎没有通过它显示的实际磁盘。

除了消耗一些内存之外，这不应该有害；但是您可以要求VMware主机管理员检查VM的配置，并从虚拟硬件配置中删除当前未使用的虚拟SATA控制器，除非不需要。

也许主机管理员试图在以前的维护中断时升级控制器类型，但是必须回滚更改，因为您的VM没有配置为支持VMware PVSCSI或任何其他更现代的磁盘控制器类型。

为了获得最大的性能，PVSCSI似乎是最好的选择.，因为它消除了VM和主机之间的工作重复。

Answer 2

我在vmware上也遇到了类似的问题，当时我根本没有安装任何SCSI设备，但是linux却显示出难以置信的数量，比如/dev/sdg。我的磁盘是IDE，所以我想出了编辑machine.vmx并从scsi0.present = "TRUE"更改为"FALSE"的方法。解决了我的问题。