Unable to back up a VHD with UniTrends. Error: Snapshot chain is too long, Operation failed.

When Unitrends creates snapshots, it copies the snap shots to the Unitrends storage and then deletes the snapshot. If the delete operation fails, then every time Unitrends creates a snapshot the snapshot chain will grow in size. The snapshot chain has a maximum size of 30 snapshots. After the 30th snapshot no more can be created. The error, “Snapshot chain is too long” will appear in the Unitrends logs. You will also not be able to create a snapshot in XenCenter or from an xe command

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Citrix Hypervisor Export Running VM – Export snapshot to file through CLI

Find the VM that you want to backup: xe vm-list

Snapshot the VM, see https://docs.citrix.com/en-us/xencenter/7-1/vms-snapshots-take.html

Find the snapshot to export by listing snapshots and their corresponding VMs: xe snapshot-list params=uuid,name-label,snapshot-of

Set the snapshot to be exportable: xe snapshot-param-set is-a-template=false uuid=<snapshot uuid>

Export the snapshot to a file: xe vm-export uuid= filename=<snapshot uuid>

Later, it can be imported: xe vm-import filename=<path> preserve=true force=true sr-uuid=<uuid> (xe sr-list to find the sr uuid)

Related:

Citrix Hypervisor Export Running VM – Export snapshot to file

Find the VM that you want to backup: xe vm-list

Snapshot the VM, see https://docs.citrix.com/en-us/xencenter/7-1/vms-snapshots-take.html

Find the snapshot to export by listing snapshots and their corresponding VMs: xe snapshot-list params=uuid,name-label,snapshot-of

Set the snapshot to be exportable: xe snapshot-param-set is-a-template=false uuid=<snapshot uuid>

Export the snapshot to a file: xe vm-export uuid= filename=<snapshot uuid>

Later, it can be imported: xe vm-import filename=<path> preserve=true force=true sr-uuid=<uuid> (xe sr-list to find the sr uuid)

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How to increase disk space for MCS catalogs with VMware

When needing to expand the system drive on MCS provisioned servers with eager zeroed thick provisioning on the master image (gold image), VMware will not allow you to do this due to existing snapshots for this VM.

Also, removal of any snapshots from the master image will cause Citrix Studio to have problems as it requires access to the entire snapshot chain for the master image, and removal of a single snapshot will cause instability while it’s looking for this missing snapshot when referencing the catalog in Studio.

There is also the fact that the disk drive space is set in the provisioning scheme of the catalog upon creation, and this cannot be modified.

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Vulnerability in Java Deserialization Affecting Cisco Products

A vulnerability in the Java deserialization used by the Apache Commons Collections (ACC) library could allow an unauthenticated, remote attacker to execute arbitrary code.

The vulnerability is due to insecure deserialization of user-supplied content by the affected software. An attacker could exploit this vulnerability by submitting crafted input to an application on a targeted system that uses the ACC library. After the vulnerable library on the affected system deserializes the content, the attacker could execute arbitrary code on the system, which could be used to conduct further attacks.

On November 6, 2015, Foxglove Security Group published information about a remote code execution vulnerability that affects multiple releases of the ACC library. The report contains detailed proof-of-concept code for a number of applications, including WebSphere Application Server, JBoss, Jenkins, OpenNMS, and WebLogic. This is a remotely exploitable vulnerability that allows an attacker to inject any malicious code or execute any commands that exist on the server. A wide range of potential impacts includes allowing the attacker to obtain sensitive information.

Object serialization is a technique that many programming languages use to convert an object into a sequence of bits for transfer purposes. Deserialization is a technique that reassembles those bits back to an object. This vulnerability occurs in Java object serialization for network transport and object deserialization on the receiving side.

Many applications accept serialized objects from the network without performing input validation checks before deserializing it. Crafted serialized objects can therefore lead to execution of arbitrary attacker code.

Although the problem itself is in the serialization and deserialization functionality of the Java programming language, the ACC library is known to be affected by this vulnerability. Any application or application framework could be vulnerable if it uses the ACC library and deserializes arbitrary, user-supplied Java serialized data.

Additional details about the vulnerability are available at the following links:

Official Vulnerability Note from CERT
Foxglove Security
Apache Commons Statement
Oracle Security Alert

Cisco will release software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20151209-java-deserialization

Security Impact Rating: High

CVE: CVE-2015-6420

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Capturing the Revision History’s state in the Desktop Designer

Hi all,

Currently we do have a scenario where i was trying to move snapshots from one region to another. where i have idea to capture the information of the revision history for the track from which i am trying to migrate the snapshot from. Is there any reference to a file where i could get the revision details from?

Thanks.

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