Welcome to the “Lessi Learned” Newsletter, 2nd Edition!

Whether or not it truly counts as the first cyberattack, it’s a great reminder of how far we’ve come. Back then, the damage was minimal and mostly academic. Today, attacks are industrialized, automated, and capable of taking entire businesses offline. Which is exactly why keeping your disaster recovery systems modern, tested, and evolving isn’t just good practice — it’s essential.

So, let’s take a look at what I’ve taken away from the past few days:

The Veeam team—including Anand Eswaran, Anton Gostev, Rick Vanover, Emilee Tellez, and others—will deliver an event packed with news and insights. Deep Dive Breakout Sessions will give you everything you need to know to stay ahead.

Excited? Register now: Veeam Virtual Launch Event

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Veeam Software Appliance Access Recovery

If all Host Admin accounts or MFA credentials for your Veeam Software Appliance are lost, access recovery is still possible.

Veeam’s KB4761 outlines how to use the Veeam Live OS ISO to regain root access and reset credentials. By booting from the ISO, admins can unlock accounts or change passwords without redeploying the appliance.

This method is intended as a last-resort option when no admin login remains. To prevent lockouts, keep at least two admin accounts and include the ISO steps in your DR plan.

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Patch your systems!

Keeping your environment up to date is crucial. Here are the key updates from the past few days:

• Veeam Backup & Replication 12.3.2.4165 Patch / KB 4771

I already listed this patch in the last newsletter. Unfortunately I still see many domain joined environments without that important fix. So if you were not able to install it, it really makes sense to do it now.

• Veeam Backup for Microsoft 365 8.2 / KB4751

For the full list of enhancements please read the KB listed in the heading carefully.

What’s included in v8.2, some highlights:

• Faster retention runs on object storage repositories
• added platform support (eg. Windows Server 2025 support, RHEL 6.5 support for proxy servers,…)
• Collect product logs for a specific tenant or backup job (great feature for Service Provider)
• Improved memory usage on the Veeam Backup for Microsoft 365 controller

Beside that v8.2 delivers a number of bugfixes and some improvements in data management, talking about the Move-VBOEntityData cmdlet.

My lessons learned this week: Unlimited = 128?

I recently stumbled across an interesting fact that I wanted to share: someone expected that unchecking the box “Limit maximum concurrent tasks to…” in the Veeam Repository settings would give them truly unlimited tasks.

The surprise? “Unlimited” in the user interface actually defaults to 128 tasks. Not exactly infinite, right?

To go beyond that limit, you can use the UIMaxConcurrentTasks registry key:

• Location: HKEY_LOCAL_MACHINE\SOFTWARE\Veeam\Veeam Backup for Microsoft 365
• Type: DWORD
• Value: Set the maximum number of concurrent tasks you want (e.g., 256)

Once set, restart the Veeam Backup service, and the repository will honor the new limit.

Lesson learned: sometimes “unlimited” really is just 128 🙂

In this episode, I want to highlight a feature that has saved me more than once: Veeam’s Quick Rollback.

I’m pretty sure you know this challenge — restoring a large VM from the previous night’s backup after something went wrong (maybe even caused by the administrator himself).

What makes Quick Rollback so powerful is that it only needs to restore the small percentage of data blocks that actually changed since the last backup. The result? The VM was back online in record time — long before my coffee had a chance to cool.

🧩 How It Works: Like a Puzzle, But Faster

Imagine your VM as a puzzle made up of thousands of tiny blocks. Each block represents a piece of data. When something goes wrong—be it a botched update, a rogue application, or a user error—only a few blocks are out of place. With Quick Rollback, Veeam doesn’t rebuild the entire puzzle. Instead, it identifies and restores only the changed blocks, using VMware’s Changed Block Tracking (CBT) technology. This targeted approach means you get back to business faster, with minimal impact on your production environment

⚠️ Know When Not to Use It

Quick Rollback isn’t a one-size-fits-all solution. It’s designed for guest OS-level issues—like application errors or accidental file deletions. However, if the problem stems from VM hardware failures, storage issues, or power outages, CBT data may be unreliable, leading to potential data corruption. In such cases, a full restore is the safer bet

🧠 My summary

Veeam’s Quick Rollback is a powerful tool for rapid recovery, especially when dealing with OS-level issues. By restoring only the changed data blocks, it minimizes downtime and gets your VM back in action quickly. Just remember to assess the root cause of the issue before opting for this feature, and always ensure the necessary prerequisites are in place.

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Thanks for reading

I hope you enjoyed the 2nd edition of my Lessi-Learned Newsletter. Thank you for reading even these last lines!

Got feedback or something you want to see in the next edition? Leave a comment, write me on X (@lessi001) or connect at LinkedIn.

Welcome to the very first edition of my “Lessi Learned” Newsletter!

Wondering about the title? It is a play on ‘lessons learned’ and my nickname, Lessi.” 🙂

Here you’ll find a mix of news, insights, and random discoveries from the ever-evolving world of Veeam — sprinkled with a few personal takes and tech tidbits I stumble across along the way.

The plan is to publish every two weeks… although, as we all know, “plans” tend to compete with work, family, and the occasional spare-time adventure. Let’s see how that goes — and let’s learn something along the way together!

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• Veeam Plug-In for SAP HANA – Standalone Mode – System Requirements for x64 Linux
• Veeam Plug-In for SAP HANA – Standalone Mode – System Requirements for Linux on Power
• Veeam Plug-In for SAP HANA – Managed Mode – System Requirements

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Hypervisor Support

Support for Scale Computing SC//HyperCore is now live, while the XCP-ng integration has reached public beta—interestingly, it also seems to work with XenServer.

Interested? Check out the XCP-ng public beta here: https://lnkd.in/dfCVaC3Q

But there is more! According to Anton, the HPE VM Essentials integration is already in progress!

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Patch your systems!

Keeping your environment up to date is crucial. Here are the key updates from the past few days:

• Veeam Backup & Replication 12.3.2.4165 Patch / KB 4771
• VeeamONE 13 Patch 1 / KB 4776

My lessons learned this week:

take care if you use S3-compatible repositories for Unstructured Data and Entra ID Log backup jobs (whether primary, secondary, or archive).

Starting with v12.3.1, S3-compatible repositories are created by default with the “Create new buckets automatically” option enabled. Sounds convenient, right? Well, not for these special workloads, because Multi-Bucket repositories are not supported.

The solution is simple but crucial:

if you plan to use an S3-compatible repository for Unstructured Data or Entra ID Log backups, make sure to disable the “Create new buckets automatically” option when creating the repository. Once it’s set, you can’t change it—otherwise, that repository simply won’t work for these jobs.

Lesson learned: defaults are great… until they aren’t 😉

This allows users to resume work quickly, while older data is restored in the background.

A small checkbox, a big impact.

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Thanks for reading

Congrats, you made it to the end! 🎉

Got feedback or something you want to see in the next edition? Leave a comment, write me on X (@lessi001) or connect at LinkedIn.