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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Sophos Anti-Virus for Linux: On-Access filesystem support

This article describes the filesystems supported for on-access scanning on Linux platforms.

The following sections are covered:

Known to apply to the following Sophos product(s) and version(s)

Sophos Anti-Virus for Linux 9 and Sophos Anti-Virus for Linux 10

Good filesystems

The following filesystems are known to work with Sophos Anti-Virus for Linux:

Filesystem Name Talpa Support? Fanotify Support?
btrfs Yes Yes
cifs Yes No
ecryptfs Yes Yes
ext2 Yes Yes
ext3 Yes Yes
ext4 Yes Yes
fuse Yes Yes
fuseblk Yes Yes
iso9660 Yes Yes
jfs Yes Yes
minix Yes Yes
msdos Yes Yes
ncpfs Yes Yes
nfs Yes Yes
nfs4 Yes* No
nssadmin Yes No
oes Yes No
overlayfs Yes Yes
overlay Yes Yes
ramfs Yes Yes
reiserfs Yes Yes
smbfs Yes Yes
tmpfs Yes Yes
udf Yes Yes
vfat Yes Yes
xfs Yes Yes
zfs Yes No

*Note: Talpa does not support locally mounted (non-network) nfs4 filesystems.

Unsupported filesystems

The following filesystems are unsupported. The majority of these are pseudo-filesystems that do not contain regular files and cannot be scanned.

Filesystem Name Talpa Support? Fanotify Support? Notes
aufs No No Pseudo-filesystem
autofs No No Pseudo-filesystem
binfmt_misc No No Pseudo-filesystem
bpf No No Pseudo-filesystem
cgroup No No Pseudo-filesystem
configfs No No Pseudo-filesystem
debugfs No No Pseudo-filesystem
devfs No No Pseudo-filesystem
devpts No No Pseudo-filesystem
devtmpfs No No Pseudo-filesystem
fuse.gvfs-fuse-daemon
No No See KBA 118982
fusectl No No Pseudo-filesystem
inotifyfs No No Pseudo-filesystem
mqueue No No Pseudo-filesystem
nfsd No No Pseudo-filesystem
nsspool No No Pseudo-filesystem
proc No No Pseudo-filesystem
romfs No No Pseudo-filesystem
rootfs No No Pseudo-filesystem
rpc_pipefs No No Pseudo-filesystem
securityfs No No Pseudo-filesystem
selinuxfs No No Pseudo-filesystem
squashfs No No
subfs No No Pseudo-filesystem
sysfs No No Pseudo-filesystem
usbdevfs No No Pseudo-filesystem
usbfs No No Pseudo-filesystem

Other filesystems

Behavior with other filesystems will depend on the on-access interception method:

If you’ve spotted an error or would like to provide feedback on this article, please use the section below to rate and comment on the article.

This is invaluable for us to ensure that we continually strive to give our customers the best information possible.

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File System on Control Domain Full on XenServer

The causes of these problems and the steps to take can be different depending on the partition layout of your XenServer host. For more information about partition layouts, see https://docs.citrix.com/en-us/xenserver/current-release/install/partition-layout.html.

This section includes steps to take to free up space right now. It also includes practices that you can put in place to avoid the problem occurring in the future.

What partition layout is your host using?

  • Legacy partition layout: This partition layout allows a 4 GB partition for the Control Domain. The Control Domain partition is also used for swap and logging.

    All XenServer hosts of version 6.5 and earlier use the legacy partition layout. Some XenServer hosts of version 7.0 and later use the legacy partition layout; this is the case when the host was upgraded from XenServer 6.5 or earlier and kept its existing layout, or when the host is a small device that does not have enough space for the new partition layout.

    If the output of the df -h command shows the size of the file system mounted on / as 4 GB, your host has the legacy partition layout.
  • New partition layout: This partition layout allows a dedicated 18 GB partition for the Control Domain. Logs are saved to a separate dedicated partition. XenServer hosts with this partition layout are less likely to experience this problem.

    All XenServer hosts of version 7.0 and later have this partition layout by default. However, some hosts can use the legacy partition layout if they were upgraded from XenServer version 6.5 or earlier and kept their existing layout or if they are a small device that does not have enough space for the new partition layout.

    If the output of the df -h command shows the size of the file system mounted on / as 18 GB, your host has the new partition layout.

Freeing up space on the Control Domain filesystem now

1. Remove additional logs

Legacy partition layout only: You can clear surplus logs for all XenServer hosts, but it will free space in the Control Domain filesystem only for those hosts that have the legacy partition layout.

  1. Change directory into the /var/log directory

    # cd /var/log
  2. Remove old compressed logs (.gz files). Do not remove *.log files as this will break log rotation and requires a reboot of the host to fix.

    # rm *.gz

Refer to the following screen shot for an example command. This command ensures that all the current logs files will be intact and will not be deleted.

In the /var/log directory, command rm -rf audit.log.* messages.* SMlog.* xensource.log.* xenstored-access.log.*

2. Remove cached uploaded patch files

For XenServer 7.0 and earlier:
1. Change directory into /var/patch

# cd /var/patch

2. Remove all the entries except the “/applied” folder

3. Use the following command to remove all the uploaded patches and without deleting the applied folder

# find /var/patch -maxdepth 1 -type f -exec rm -v {} +
For XenServer 7.1 and later:
1. Change directory into /var/update

# cd /var/update

2.
Remove all the entries except the "/applied" folder

3. Use the following command to remove all the uploaded patches and without deleting the applied folder


# find /var/update -maxdepth 1 -type f -exec rm -v {} +

3. Remove the patch-backups

  1. cd /opt/xensource/patch-backup
  2. ls
  3. rm -rf *

In the /opt/xensource/patch-backup directory, command rm -rf

4. Remove stunnel entries

1. Change to the tmp directory

# cd /tmp/

2. Remove any old stunnel log entries


In the /tmp directory, command rm -rf stunnel0* stunnel8* stunnelf*

Note: If these steps do not reflect the space being cleared, run #service syslog restart and the usage inside the root file system will be cleared.

5. Remove additional files

  • Check /tmpdirectory for any rogue files. You can delete everything inside it as XenServer won't store any default files in it.

  • Check "~" and "/" to see if there are any additional ISO files or any extra packages are present inside the directory. If yes, delete them.

Even after executing all those above steps if the space is still not reclaimed, contact Citrix Technical support.

Avoiding a full Control Domain file system in the future

The following practices to manage your logs reduce the used space in your control domain only if you are using the legacy partition layout.

Enable Log Compression

  1. Open the /etc/logrotate.conf file by using a text editor (for example, nano).
  2. Remove the comment symbol (#) from the #compress line so that it reads compress:
  3. Save the file and exit text editor. (In nano, press CTRL+O to save, and CTRL+X to exit). XenServer uses the new configuration from the next time.

Rotate your logs

For more information, see https://support.citrix.com/article/CTX238919.

Store your logs on a separate file system

For more information, see https://support.citrix.com/article/CTX130245.

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Sophos Anti-Virus for Linux: Savscan resets time to 0 millisecond

This article provides information about how Sophos Anti-Virus for Linux modifies the atime and mtime of a given file after it has been scanned with savscan.

Applies to the following Sophos product(s) and version(s)

Sophos Anti-Virus for Linux

## atime

# ls -lu --full-time /tmp/folder/

-rw-r--r-- 1 root root 107 <date> 15:30:46.492277736 +0900 file001

## mtime

# ls -l --full-time /tmp/folder/

-rw-r--r-- 1 root root 107 <date> 15:30:46.491277717 +0900 file001

## ctime

# ls -lc --full-time /tmp/folder/

-rw-r--r-- 1 root root 107 <date> 15:30:46.493277755 +0900 file001

The timestamp for the atime and mtime is reset to the millisecond value of .000000000

# savscan /tmp/folder/

SAVScan virus detection utility

Version 5.5X.Y [Linux/AMD64]

Virus data version 5.XY, Month Year

Includes detection for 30928050 viruses, Trojans and worms

Copyright (c) 1989-2019 Sophos Limited. All rights reserved.

<timestamp>

IDE directory is: /opt/sophos-av/lib/sav

Using IDE file [..]

Quick Scanning

1 file scanned in 19 seconds.

No viruses were discovered.

End of Scan.

## atime

# ls -lu --full-time /tmp/folder/

-rw-r--r-- 1 root root 107 <date> 15:30:46.000000000 +0900 file001

## mtime

# ls -l --full-time /tmp/folder/

-rw-r--r-- 1 root root 107 <date> 15:30:46.000000000 +0900 file001

## ctime

# ls -lc --full-time /tmp/folder/

-rw-r--r-- 1 root root 107 <date> 15:35:11.171369753 +0900 file001

Note: The above example shows that the atime and mtime values for a file are rounded down to the nearest second.

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This is invaluable for us to ensure that we continually strive to give our customers the best information possible.

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Ghost error during restoring

I need a solution

Good morning, Inside the company i work for we got many cnc siemens machines with a pc windows 7 and the ghost suite integrated. After a blackuot i made a backup of the 2 partitions contained inside the ssd and after that i tried to restore an old partition backup. Here i made an error, i pressed restore entire hdd and i choose the partition file. After 2 seconds i got an error from the ghost console. Now, i got the hdd without anything inside. I think the procedure canceled some configuration files but no real files. Windows does not start and during the boot up i only got a black screen. Do you know any way to try to recover the hdd?

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Missing partition resize options

I need a solution

Hi guys,

We’re trying to update our win10 master and captured our customized installation. We don’t have any problem with the capture, no errors or warning. When I try to create a deployment task (using a copy of the one we use for our 1803 master), I can add the *.gho I’ve just created. But when I go to the advanced options for resizing partitions, none are listed (I should have 3 listed). The 3 partitions are created if I use the *.gho but I really need to resize them.

Does someone here ever encountered this problem ? What am I missing ? Thanks for your help !

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Difference between partition admin users configured on Default partition and Admin Partition

Question: What is the difference between partition admin users configured on Default partition from the ones created on Admin Partition?

Answer:

1) AP users configured from Default partition are first created on Default partition and then bound to a Admin partition.

But for the other case, you need to first switch to the admin partition and create the user in that partition itself.

2) You can only login to ADC through NSIP and SNIP of default partition using the default partition user admin . Whereas you can only login to ADC through SNIP of Admin partition using admin partition created user.

3) You can bind user defined command policies for default partition user. But for admin partition specific user can have only 4 pre-defined command policies to choose from.

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