Iscsi for Virtual Machine Storage in Proxmox

[larryd]

We are our wits end trying to get Iscsi working reliably in Proxmox 9.1 VE. We have installed all required components and are connected to a Storage Lun on our Iscsi Target Server. However every time we install a Windows Virtual Machine using that Lun for storage; the install begins normally but eventually fails and the VG becomes unavailable.
We are using the same Iscsi Target Server using different Luns for Esxi8 and Ubuntu Server 26.10 and both have no issues and the Iscsi Storage is consistent and
reliable. We have come across articles that some say older versions of Proxmox Iscsi Storage worked reliably but newer versions have bugs.
Any ideas would be welcome to determine the cause of this.

 

[bbgeek17]

Hi @larryd, welcome to the forum.

Its hard to provide ideas as there is not enough technical information in your post. Answering the following questions may assist members to provide some guidance:

- What type of storage are you using? (Vendor, model)
- What type of connectivity?
- What is the network layout?
- How is the PVE storage pool configured? (cat /etc/pve/storage.cfg)
- What exact errors do you see in the VM?
- Are there message in "dmesg" and "journalctl" of the PVE host that correspond in time to the failure?
- What exactly does "VG becomes unavailable" mean?
- Have you followed your storage vendor guide for best practices in PVE connectivity?

As iSCSI is handled at the Kernel level and PVE is using Ubuntu-derived Kernel, you may need to employ a network trace analysis.

PS we have customers running from PVE6 to 9-latest using iSCSI - we have not seen any issues with the protocol itself.

PPS you may find these articles helpful:
https://kb.blockbridge.com/technote/proxmox-tuning-low-latency-storage/index.html
https://kb.blockbridge.com/technote/proxmox-lvm-shared-storage/

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[larryd]

Hi @larryd, welcome to the forum.

Its hard to provide ideas as there is not enough technical information in your post. Answering the following questions may assist members to provide some guidance:

- What type of storage are you using? (Vendor, model)
- What type of connectivity?
- What is the network layout?
- How is the PVE storage pool configured? (cat /etc/pve/storage.cfg)
- What exact errors do you see in the VM?
- Are there message in "dmesg" and "journalctl" of the PVE host that correspond in time to the failure?
- What exactly does "VG becomes unavailable" mean?
- Have you followed your storage vendor guide for best practices in PVE connectivity?

As iSCSI is handled at the Kernel level and PVE is using Ubuntu-derived Kernel, you may need to employ a network trace analysis.

PS we have customers running from PVE6 to 9-latest using iSCSI - we have not seen any issues with the protocol itself.

PPS you may find these articles helpful:
https://kb.blockbridge.com/technote/proxmox-tuning-low-latency-storage/index.html
https://kb.blockbridge.com/technote/proxmox-lvm-shared-storage/

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

Installed Promox 9.1 new from scratch and configured Iscsi storage and then ran pvcreate and vgcreate so we have an LVM on top of Iscsi (using 10GB network for Iscsi) and then installed Windows 2022 Server which finished installing without any issues. We are using Kernsafe iStorage Server for the Iscsi target which we have used for many years without issue. The performance running the VM is good and is almost equal to Iscsi on Ubuntu Server. ESXi8 performance using Iscsi is better than Promox and Ubuntu Server. We have no pools configured in Proxmox. The reason for us doing this is to compare Proxmox Iscsi performance with ESXi8 and Ubuntu Server and now we can happily say the mission is complete! The VG is unavailable error was displayed on in the GUI tasks our previous Promox 9.1 install when tried multiple times to install a Windows 2022 Server VM on Iscsi Storage.

 

[alexskysilk]

The VG is unavailable error was displayed on in the GUI tasks our previous Promox 9.1 install when tried multiple times to install a Windows 2022 Server VM on Iscsi Storage.

post logs from the storage and host for the timeperiod the drop occured. it would also be good to look at your /etc/network/interfaces file, as well as your network setting from the storage (not just ip but connection speed and mtu)

I'm guessing you have network issues.

 

[bbgeek17]

I'm guessing you have network issues.

Sounds like they resolved the problem. I agree that their original issue was likely network configuration related, perhaps MTU was misconfigured.

We have no pools configured in Proxmox.

Your iSCSI storage is a "storage pool" of iSCSI type in PVE speak. The LVM storage is the LVM storage pool.

Happy to hear that you have it under control. You can mark the thread as Solved by editing the first post in the thread and selecting the appropriate prefix from the subject dropdown.

Cheers.

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox