====== iSCSI ======

Proxmox doc recommends:

  iSCSI is a block level type storage, and provides no management interface. 
  So it is usually best to export one big LUN, and setup LVM on top of that LUN. 
  You can then use the LVM plugin to manage the storage on that iSCSI LUN.

iSCSI target/direct is capable to store only following content types
  * images
  * none

Options during adding iSCSI storage:
  * **Use LUNs directly** - use directly as VM disk without putting LVM volume on it.

===== Create LVM on iSCSI =====
  * add iSCSI device - do not select **Use LUNs directly**
  * add LVM
    * base storage: select just added iSCSI LUN
DRAFT

    Click 'Add LVM Group' on the Storage list
    As storage name use whatever you want but take care, this name cannot be changed later.
    For 'Base Storage', use the drop down menu to select the previously defined iSCSI target.
    For 'Base Volume' select a LUN
    For 'Volume Group Name' give a unique name (this name cannot be changed later).
    Enable shared use (recommended)
    Click save


DRAFT


===== NAS326 CHAP issue =====

NAS326 requires CHAP authentication and initiator user name.
There are 2 options to use NAS326:
  * disable CHAP on NAS326
  * enable CHAP on Proxmox

Proxmox initiator name can be found in file: ''/etc/iscsi/initiatorname.iscsi''

==== disable CHAP on NAS326 ====

It exposes LUN to everybody in network. Use it only in separate LANs!!!

[[https://wiki.archlinux.org/index.php/ISCSI/LIO#Disable_Authentication|Disable Authentication]]
[[http://linux-iscsi.org/wiki/ISCSI#Define_access_rights]]

It is possible to define common login information for all Endpoints in a TPG: [[http://linux-iscsi.org/wiki/ISCSI#TPG_authentication|TPG authentication]]

How to disable security on NAS326 (enable iSCSI demo mode)

  * create the LUN(s) and target via the webgui
  * login to your zyxel via ssh as root
  * \\ <code bash>
targetcli ls
targetcli /iscsi/iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux/tpg1/ get attribute
targetcli /iscsi/iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux/tpg1/ set attribute authentication=0 demo_mode_write_protect=0 generate_node_acls=1 cache_dynamic_acls=1
targetcli saveconfig
</code>


==== use CHAP on Proxmox ====

Logout and remove all failed trials to connect to NAS326. 
Especially if IPv6 was enabled on NAS326, proxmox detect two send_targets: one for IPv4 and one for IPv6 (not reachable).
After disabling IPv6 on NAS326, please delete IPv6 target portal:
<code bash>
targetcli ls
targetcli /iscsi/iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux/tpg1/portals ls
targetcli /iscsi/iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux/tpg1/portals/ 'delete fd57::be99:11ff:fe06:18b0 3260'
targetcli saveconfig
</code>

<code bash>
ls /etc/iscsi/nodes

# logout
iscsiadm -m node -u -T "iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux" --portal 192.168.28.150
iscsiadm -m node -u -T "iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux" --portal fd57::be99:11ff:fe06:18b0
# remove
iscsiadm -m node -o delete -T "iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux" --portal 192.168.28.150
iscsiadm -m node -o delete -T "iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux" --portal fd57::be99:11ff:fe06:18b0
</code>

Uncomment and set following config lines:
<file conf | /etc/iscsi/iscsid.conf>
node.session.auth.authmethod = CHAP
# get initiator name from /etc/iscsi/initiatorname.iscsi
node.session.auth.username = iqn.1993-08.org.debian:01:4dad9d97a329
node.session.auth.password = my_chap_password_for_NAS326
</file>

Now discovery should return only one IPv4 target:
<code bash>
# iscsiadm -m discovery -t sendtargets -p 192.168.28.150
192.168.28.150:3260,1 iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux

# list config options
iscsiadm -m node -o show

# login
iscsiadm -m node --login
Logging in to [iface: default, target: iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux, portal: 192.168.28.150,3260] (multiple)
Login to [iface: default, target: iqn.2020-04.com.zyxel:nas326-iscsi-pve1-isos-target.tjlintux, portal: 192.168.28.150,3260] successful.

# check new block device
cat /proc/partitions

iscsiadm -m node --logout
</code>

Now add iSCSI from webui.


  

iSCSI+LVM supports HA and Live Migration of VMs --> mark LVM storage as shared