■debian12のKVMホストから、targetcliでディスクストレージをサービスとして提供
$ lsb_release -d
No LSB modules are available.
Description: Debian GNU/Linux 12 (bookworm)
■仮想マシンが認識できるストレージをKVM経由でiscsiadmを使って接続
$ virsh list
Id 名前 状態
-----------------------------
3 kvm-debian12 実行中
■まずはtargetcliをインストール
$ apt-file search bin/targetcli
targetcli-fb: /usr/bin/targetcli
targetcli-fb: /usr/bin/targetclid
$ dpkg -l targetcli-fb | grep ^ii || sudo apt-get install -y targetcli-fb
■タブ補完が使える、専用のシェルで操作する
$ sudo targetcli
targetcli shell version 2.1.53
Copyright 2011-2013 by Datera, Inc and others.
For help on commands, type 'help'.
/> <tab>
* / backstores/ iscsi/ loopback/ vhost/ xen-pvscsi/ bookmarks
cd clearconfig exit get help ls pwd refresh
restoreconfig saveconfig sessions set status version
/> version
targetcli version 2.1.53
■「Storage Objects」で設定したディスクを「Targets」の方式で提供できる
$ sudo targetcli ls /backstores/ | awk '/Storage/{print $2,$(NF-2),$(NF-1),$NF}'
block [Storage Objects: 0]
fileio [Storage Objects: 0]
pscsi [Storage Objects: 0]
ramdisk [Storage Objects: 0]
$ sudo targetcli ls / | awk '!/Storage/&&/Targets/{print $2,$(NF-1),$NF}'
iscsi [Targets: 0]
loopback [Targets: 0]
vhost [Targets: 1]
xen-pvscsi [Targets: 0]
■ストレージの選択肢のうち、テストでfileioを使うとする
※「pscsi」は上級ユーザ向けらしいので、わかる人だけが触っているはず
○block：/dev/sdX
●fileio：ddで作ったimg
○ramdisk：メモリ上に作ったファイル
■ターゲットとしてサービスを提供する選択肢のうち、KVM経由で仮想マシンに提供できるvhostを選択
※xen-pvscsiはXen向けなので触れない
※vhostのkernel moduleがなければ「naa.」が「iqn.」になるが、iscsiを使用する方針とする。
○iscsi
○loopback
●vhost
■まずはシンプロビジョニング的なイメージを作成
[ストレージオブジェクトの種類]_[提供方法].img
$ dd if=/dev/zero of=fileio_vhost.img count=0 bs=1 seek=2G
0+0 records in
0+0 records out
0 bytes copied, 0.000203523 s, 0.0 kB/s
$ du fileio_vhost.img
0 fileio_vhost.img
■「ストレージオブジェクトの種類」に沿って、どのディスクを公開したいのかを指定
/> /backstores/fileio
/backstores/fileio> create name=fileio_vhost file_or_dev=fileio_vhost.img size=2G
fileio_vhost.img exists, using its size (2147483648 bytes) instead
Created fileio fileio_vhost with size 2147483648
/backstores/fileio> cd fileio_vhost/
/backstores/f...ileio_vhost> <tab>
/ @last alua/ bookmarks cd exit get help info ls pwd
refresh saveconfig set status version
/backstores/f...ileio_vhost> info
aio: False
dev: fileio_vhost.img
name: fileio_vhost
plugin: fileio
size: 2147483648
write_back: True
wwn: b8d1643a-3dbb-49d6-830d-ed35759302c0
/> ls
o- / ......................................................................................................................... [...]
o- backstores .............................................................................................................. [...]
| o- block .................................................................................................. [Storage Objects: 0]
| o- fileio ................................................................................................. [Storage Objects: 1]
| | o- fileio_vhost ....................................................... [fileio_vhost.img (2.0GiB) write-back deactivated]
| | o- alua ................................................................................................... [ALUA Groups: 1]
| | o- default_tg_pt_gp ....................................................................... [ALUA state: Active/optimized]
| o- pscsi .................................................................................................. [Storage Objects: 0]
| o- ramdisk ................................................................................................ [Storage Objects: 0]
o- iscsi ............................................................................................................ [Targets: 0]
o- loopback ......................................................................................................... [Targets: 0]
o- vhost ............................................................................................................ [Targets: 0]
o- xen-pvscsi ....................................................................................................... [Targets: 0]
/> cd vhost
/vhost> info
Fabric module name: vhost
ConfigFS path: /sys/kernel/config/target/vhost
Allowed WWN types: naa
Fabric module features: nexus, acls, tpgts
Corresponding kernel module: tcm_vhost
/vhost> create
Created target naa.5001405e73b2348b.
Created TPG 1
/vhost> info
Fabric module name: vhost
ConfigFS path: /sys/kernel/config/target/vhost
Allowed WWN types: naa
Fabric module features: nexus, acls, tpgts
Corresponding kernel module: tcm_vhost
/vhost> status
Status for /vhost: Targets: 1
/vhost> ls
o- vhost .............................................................................................................. [Targets: 1]
o- naa.5001405e73b2348b ................................................................................................ [TPGs: 1]
o- tpg1 .................................................................................... [naa.50014055541d38b1, no-gen-acls]
o- acls ............................................................................................................ [ACLs: 0]
o- luns ............................................................................................................ [LUNs: 0]
/vhost> cd naa.5001405e73b2348b/tpg1/luns
/vhost/naa.50...48b/tpg1/luns> create /backstores/fileio/fileio_vhost
Created LUN 0.
/vhost/naa.50...48b/tpg1/luns> ls
o- luns .................................................................................................................. [LUNs: 1]
o- lun0 .......................................................... [fileio/fileio_vhost (fileio_vhost.img) (default_tg_pt_gp)]
■以下を参考に「naa.〜」をホストから仮想マシンにわたす
libvirt: Host Setup
$ sudo targetcli ls /vhost/
o- vhost .............................................................................................................. [Targets: 2]
o- naa.500140522c7d4e1e ................................................................................................ [TPGs: 1]
| o- tpg1 .................................................................................... [naa.5001405a28b9c6c7, no-gen-acls]
| o- acls ............................................................................................................ [ACLs: 0]
| o- luns ............................................................................................................ [LUNs: 1]
| o- lun0 .................................................... [fileio/fileio_storage (fileio_storage.img) (default_tg_pt_gp)]
$ virsh dumpxml kvm-debian12 | grep -B1 -A3 -i naa
<hostdev mode='subsystem' type='scsi_host' managed='no'>
<source protocol='vhost' wwpn='naa.500140522c7d4e1e'/>
<alias name='hostdev0'/>
<address type='pci' domain='0x0000' bus='0x07' slot='0x00' function='0x0'/>
</hostdev>