Loading

×Sorry to interrupt
CSS Error

Refresh

Cookie Preference Center

General Information on cookies

When you visit our website, we use cookies to ensure that we give you the best experience. This information does not usually directly identify you, but it can give you a more personalized web experience. Because we respect your right to privacy, you can choose not to allow some types of cookies by clicking on the different category headings to find out more and change your settings. However, blocking some types of cookies may impact your experience on the site and the services we are able to offer. Further information can be found in our

Cookie Policy.

Strictly Necessary

Strictly Necessary

Always Active

Strictly Necessary

Strictly necessary cookies are always enabled since they are essential for our website to function. They enable core functionality such as security, network management, and website accessibility. You can set your browser to block or alert you about these cookies, but this may affect how the website functions. For more information please visit www.aboutcookies.org or www.allaboutcookies.org.

Cookie Details‎

Performance

Performance

Performance

Performance cookies are used to analyze the user experience to improve our website by collecting and reporting information on how you use it. They allow us to know which pages are the most and least popular, see how visitors move around the site, optimize our website and make it easier to navigate.

Cookie Details‎

Please confirm your settings by refreshing the page.

Functional

Functional

Functional

Functional cookies help us keep track of your past browsing choices so we can improve usability and customize your experience. These cookies enable the website to remember your preferred settings, language preferences, location and other customizable elements such as font or text size. If you do not allow these cookies, then some or all of these services may not function properly.

Cookie Details‎

Advertising

Advertising

Advertising

Advertising cookies are used to send you relevant advertising and promotional information. They may be set through our site by third parties to build a profile of your interests and show you relevant advertisements on other sites. These cookies do not directly store personal information, but their function is based on uniquely identifying your browser and internet device.

Cookie Details‎

Advertising Cookies

Consent Leg.Interest

Select All Vendors

Select All Vendors

Select All Hosts

Select All

Clear Filters

Information storage and access

Apply

Confirm My Choices Reject All Allow All

My Subscriptions

Loading

Knowledge Base

Reverting to a preexisting snapshot can cause incremental backups based on Changed Block Tracking to become inconsistent (1021607)

Last Updated: 3/20/2024Categories: Total Views: 19670Language:
English

1 like this article

Subscribe to get an email
newsletter with new updates

1 people found this helpful Please provide article feedback:

Symptoms

Reverting a snapshot for a virtual machine that has Changed Block Tracking (CBT) enabled to a snapshot older than its last incremental backup can cause inconsistencies in incremental backups of that virtual machine.

Note: Backup products that take advantage of CBT may be affected. Check with your backup vendor.

The following scenario must occur, in sequence, before there is a possibility of this issue occurring:

A virtual machine with hardware version 7 must have a snapshot present and must have been previously backed up by a backup product leveraging CBT.

A backup product performs an incremental backup of the virtual machine and employs CBT to determine changed blocks since the last backup.

After the incremental backup is complete, you manually revert a snapshot on the virtual machine.

A backup product performs an incremental backup of the virtual machine and employs CBT to determine changed blocks since the last backup.

Resolution

If you need to revert a snapshot of a virtual machine (that is being backed up by a CBT-based backup application) to a snapshot older than its last incremental backup, you must do a full backup of that virtual machine before using incremental backups again.

This issue is resolved in vSphere 4.1 and vSphere 4.0 Update 3. Rather than potentially providing incomplete data, a change ID obtained before the snapshot revert is now correctly considered as being invalid.

To workaround this issue in earlier vSphere releases, perform a full virtual machine backup after a snapshot revert operation. If the backup application does not allow this as an option, you need to remove the CTK files for that virtual machine. The CTK files are stored with the virtual machine on the datastore and can be removed via the Datastore Browser. This delete operation can be safely done while the virtual machine is running.

Detectable by VMware SkylineTM

Actions

Copy

link to clipboard
copied!

Print

Language:
English

Attachments

Additional Resources

KB
•
End Of General Availability of the Free vSphere Hypervisor (ESXi 7.x and 8.x) (2107518)

Result 1 of 1

Ask The Community

Get answers quickly from VMware experts in the community

Post Subject

CONTINUE IN COMMUNITIES

Related Products:

VMware vSphere ESXi

VMware ESX Server

VMware Data Recovery

Related Versions:

VMware ESXi 4.0.x Installable

VMware ESXi 4.0.x Embedded

VMware ESX 4.0.x

VMware Data Recovery 1.x

Take Our Survey

Support Assistant