iSCSI overlay for Primera / Alletra Storage MP on CloudStack 4.22.1.1 KVM

[dahampere]

I put together an overlay that makes CloudStack’s existing Primera primary-storage path work on iSCSI-only KVM hosts.

Repo: https://github.com/dahampere/cloudstack-primera_alletraMP-iscsi
Release: https://github.com/dahampere/cloudstack-primera_alletraMP-iscsi/releases/tag/v4.22.1.1-1
License: Apache License 2.0 (derived from ACS plugins/storage/volume/primera and scripts/storage/multipath)

This is not an official Apache CloudStack release and not a new storage API.

The problem

Stock CloudStack already manages HPE Primera, 3PAR, Alletra Storage MP, and Alletra 9000 over WSAPI v1 as Provider = Primera.

The in-tree KVM host scripts only rescan Fibre Channel (/sys/class/fc_host). On an iSCSI-only hypervisor that directory is empty, so attach never sees the LUN.

A second issue: one target IQN carries many VLUNs. Logging out of the iSCSI session when a single volume detaches drops every other volume on that target.

ACS Protocol = iSCSI (one shared LUN) is the wrong control plane for this. Use Provider = Primera (or the optional AlletraMP alias below). Path format stays type=FIBERWWN; address=<WWN>.

This is not Nimble OS (Alletra 5000 / 6000).

What it does

Two pieces. You can install only the first.

Piece	Where	What
iSCSI connect overlay (required)	every KVM host	Debian package that overlays connectVolume.sh, disconnectVolume.sh, and multipath-common.sh. Rescans iSCSI sessions instead of FC. Does not log out the target on detach.
AlletraMP provider (optional)	every management node	Sidecar JAR next to Linstor/Storpool. Registers the same Primera adapter as AlletraMP so Add Primary Storage can show that name. Existing provider=Primera pools are left alone.

Stock Primera stays installed. Do not rewrite cloudstack-*.jar and do not SQL-rename existing pools.

If multipath.conf uses user_friendly_names yes (maps as mpathX), the overlay creates /dev/mapper/3<wwn> → that device so CloudStack still finds the volume.

Scope and status

• Pinned to Apache CloudStack 4.22.1.1 Debian/Ubuntu packages. Not “any 4.22”. No RPM.
• Hypervisor: KVM.
• Array: Primera / 3PAR / Alletra Storage MP / Alletra 9000, WSAPI v1, iSCSI.
• Proven on this package: deploy, attach, detach, live migrate.
• Not in the KVM overlay (stock FC scripts remain): resizeVolume.sh, copyVolume.sh, cleanStaleMaps.sh. Resize / copy / stale-map cleanup on iSCSI is unproven here.

How to try it

Full steps: docs/INSTALL.md

Short version:

1. On the array: host object per KVM hypervisor (name = CloudStack hostname), register each host IQN, put hosts in one host-set, note CPG + WSAPI URL.
2. On every KVM host: open-iscsi + multipath-tools, discover/login to this array’s target IQN only, node.startup = automatic. Do not log that target out.
3. Install the host overlay:

sudo apt-get install ./cloudstack-alletra-mp-kvm_4.22.1.1-1_all.deb
grep -c mp_scan_lun /usr/share/cloudstack-common/scripts/storage/multipath/connectVolume.sh
# expect 1