Tag Archives: backup

Backup your systems with urBackup

In addition to my ZFS snapshots I decided to implement a secondary backup system. I decided to land on urbackup for ease of use and, more importantly, it was easier to set up.

Server Install

Assuming a Cent-based system:

cd /etc/yum.repos.d/
sudo wget http://download.opensuse.org/repositories/home:uroni/CentOS_7/home:uroni.repo
sudo yum -y install urbackup-server
sudo systemctl enable urbackup-server
sudo systemctl start urbackup-server

Open up necessary ports for the server:

sudo firewall-cmd --add-port=55413-55415/tcp --permanent
sudo systemctl reload firewalld

By default urbackup listens on port 55414 for connections. You can change this to port 80 and/or 443 for HTTPS by installing nginx and having it proxy the connections for you.

sudo yum -y install nginx
sudo systemctl enable nginx
sudo setsebool -P httpd_can_network_connect 1 #if you're using selinux

Copy the following into /etc/nginx/conf.d/urbackup.conf (make sure to change server_name to suit your needs)

server {
        server_name backup;

        location / {
                proxy_pass http://localhost:55414/;

Then start nginx:

sudo systemctl start nginx

You should then be able to access the urbackup console by navigating to the IP / hostname of your backup server in a browser.

Client Install:

Urbackup can use a snapshot system known as dattobd. You should use it if you can in order to get more consistent backups, otherwise urbackup will simply copy files from the host which isn’t always desirable (databases, for example)

Install dattobd (optional):

sudo yum -y update
# reboot if your kernel ends up being updated
sudo yum -y localinstall https://cpkg.datto.com/datto-rpm/repoconfig/datto-el-rpm-release-$(rpm -E %rhel)-latest.noarch.rpm
sudo yum -y install dkms-dattobd dattobd-utils

Install urbackup client:

TF=`mktemp` && wget "https://hndl.urbackup.org/Client/2.1.15/UrBackup%20Client%20Linux%202.1.15.sh" -O $TF && sudo sh $TF; rm $TF
#Select dattobd when prompted if desired

Configure Firewall:

sudo firewall-cmd --add-port=35621-35623/tcp --permanent
sudo systemctl reload firewalld

Once a client is installed, assuming they’re on the same network as the backup server, they will automatically add themselves and begin backing up. If they don’t show up it’s usually a firewall issue.


Restoration of individual files is easily done through the web console. If you have a windows system, restoring from an image backup is also easy.

Linux hosts

Recovery is trickier if you want to restore a Linux system. Install an empty system of same distribution. Give it the same hostname. Install the client as outlined above, then run:

sudo /usr/local/bin/urbackupclientctl restore-start -b last


If for some reason the client not showing up after removing it from the GUI: Uninstall & re-install client software

sudo /usr/local/sbin/uninstall_urbackupclient
TF=`mktemp` && wget "https://hndl.urbackup.org/Client/2.1.15/UrBackup%20Client%20Linux%202.1.15.sh" -O $TF && sudo sh $TF; rm $TF

Manually update firmware on Nexus devices

The release of Android 6.0.1 had me excited because it enables LTE band 12 for my phone, the Nexus 5X, which currently uses T-mobile. Band 12 is in the 700mhz range which should greatly increase speed and coverage. I’m too impatient to wait for the OTA!

This tutorial will walk you through how to manually backup, unlock, flash, re-lock, and restore a Google Nexus 5X, but the procedure is pretty much the same for any Nexus device.

First, obtain two necessary Android development tools: adb and fastboot. Do not use your distribution’s versions of these tools – they are likely out of date. Instead, download the Android SDK directly from Google by going here and scrolling to the bottom of the page. Java is required for the sdk to install – install it if you haven’t already. Thanks to this site for explaining how to only obtain platform-tools.

sudo apt-get install openjdk-7-jre
tar zxvf android-sdk_r24.4.1-linux.tgz
android-sdk-linux/tools/android update sdk --no-ui --filter 1,platform-tools

Once you have platform-tools you need to add them to your PATH to make scripts run adb successfully (thanks to this site for the information). When you run the command below make sure to update /path/to/… to the folder where you extracted the android-sdk.

echo "export PATH=$PATH{}:/path/to/android-sdk/tools:/path/to/android/platform-tools" >> ~/.bashrc
source ~/.bashrc

Next, obtain the latest firmware for your device from the google developers site. Extract it somewhere you will remember for later.

Now, enable USB debugging on your phone if you haven’t already (thanks to this site for the info.) To do this, go to Settings / About phone, scroll to the bottom and press on the build number 7 times. Press back and go to developer options, and enable USB debugging and enable OEM unlocking. Then plug in your phone to the computer with adb installed and run this command (thanks to xda for the information)

adb backup -apk -shared -all -f <backup_filename>

Confirm the on-screen prompt on your phone. Make sure you specify a password for encryption. The above command should backup everything, but in my case it did not backup files in the flash partition (downloads, pictures, etc). Make sure you manually copy any important files from your phone before you proceed.

My first attempt at the above command didn’t work for me. I received the error message:

adb: unable to connect for backup

When I ran adb devices it showed this:

List of devices attached 
00c739918fbf4e2a offline

It turns out I had an old version of adb installed. Make sure you download Google’s official SDK instead of relying on your distribution’s version.

Once the backup is complete, you then need to reboot your phone into fastboot mode:

adb reboot bootloader

Wait for the reboot, then run the following command. Warning: this command will wipe your device. Make sure you have a reliable backup and confirm the message on your phone screen.

fastboot oem unlock

Now, navigate to the directory where you extracted your latest firmware and execute the flash-all script:

cd bullhead-mmb29k

After some time your phone will reboot into your shiny new updated OS. Skip everything setup-wise. Re-enable developer mode and android debugging, and then re-lock your bootloader:

adb reboot bootloader
fastboot oem lock

Lastly, we need to restore everything from the backup we made and re-lock the bootloader for security. Once again skip everything setup-wise on the phone, re-enable developer mode and android debugging, and then restore your stuff:

adb restore <filename>

Don’t forget to manually copy back any flash files you manually backed up earlier.

The very last (optional) step is to go into developer options settings and disable OEM unlocking.


Xenserver SSH backup script

Citrix Xenserver is an amazing hypervisor with pretty much every function released to you for free. One thing they do not handle, however, is automated backups.

I have hacked together a backup script for myself that seems to work fairly well. It is my own mix of this and this script along with some logic for e-mail reporting that I came up with myself. It does not require any modification of the xenserver host at all (no need to mount anything!) with the exception of adding a public key to the xenserver’s authorized_keys file.

This script can be run on anything with BASH and the appropriate UNIX tools (even other xenservers if you want) and uses SSH to initiate and transfer the backups to a location of your choosing.

Place this script on the machine you want to be initiating / saving the backups on. It requires that you generate an SSH public/private key pair, which can be done with this command:


Add the resulting .pub file’s contents to your xenserver’s /root/.ssh/authorized_keys file (create it if it doesn’t exist.) Take note of the location of the private key file that was generated with that command and put that path in the script.

You can download the script here or view it below. This script has been working pretty well for me. Note it will not work with any VMs that have spaces in their names. I was too lazy to debug this so I just renamed the problem VMs to remove the spaces. Enjoy!


# Modified August 30, 2015 by Nicholas Jeppson
# Taken from http://discussions.citrix.com/topic/345960-xenserver-automated-snapshots-script/ and modified to allow for ssh backups
# Additional insight taken from https://github.com/cepa/xen-backup

# [Usage & Config]
# This script involves two computers: a xenserver machine and a backup machine.
# Put this script on the backup server and run with any account that has privileges to the desired export directory.
# This script assumes you have already created a private and public key pair on the backup server
# as well as adding respective the public key to the xenserver authorized_keys file.
# [How it works]
# Step1: Snapshots each VM on the xen server
# Step2: Backs up the snapshots to specified location
# Step3: Deletes temporary snapshot created in step 1
# Step4: Deletes old VM backups as defined later in this file
# [Note]
# This script will only work with VMs that don't have spaces in their names
# Please make sure you have enough disk space for BACKUP_PATH, or backup will fail
# Tested on xenserver 6.5
# Modify the variables in the config section below to suit your particular environment's needs.

############### Config section ###############

#Location where you want backups to go

#SSH configuration

#Number of backups to keep

#Xenserver ssh configuration
#This dictates the address and location of keyfiles as they reside on the xenserver

#E-mail configuration
EMAIL_SUBJECT="`hostname -s | awk '{print "["toupper($1)"]"}'` VM Backup Report: `date +"%A %b %d %Y"`"

########## End of Config section ###############


#Replace any spaces found with backslashes because dd doesn't like them
BACKUP_PATH_ESCAPED="`echo $BACKUP_PATH | sed 's/ /\\\ /g'`"

# SSH command
remote_exec() {
chmod 0600 $XEN_KEY_LOCATION
ssh -i $XEN_KEY_LOCATION -o "StrictHostKeyChecking no" -c $SSH_CIPHER $XEN_USER@$XEN_ADDRESS $1

backup() {
echo "======================================================"
echo "VM Backup started: `date`"
begin="$(date +%s)"
echo "Backup location: ${BACKUP_PATH}"

#add a slash to the end of the backup path if it doesn't exist
if [[ "$BACKUP_PATH" != */ ]]; then

#Build array of VM names
VMNAMES=$(remote_exec "xe vm-list is-control-domain=false | grep name-label | cut -d ':' -f 2 | tr -d ' '")

echo "======================================================"
echo "$VMNAME backup started `date`"
before="$(date +%s)"

# create snapshot
TIMESTAMP=`date '+%Y%m%d-%H%M%S'`
SNAPUUID=$(remote_exec "xe vm-snapshot vm=\"$VMNAME\" new-name-label=\"$SNAPNAME\"")

# export snapshot
# remote_exec "xe snapshot-export-to-template snapshot-uuid=$SNAPUUID filename= | gzip" | gunzip | dd of="$BACKUP_PATH/$SNAPNAME.xva"
remote_exec "xe snapshot-export-to-template snapshot-uuid=$SNAPUUID filename=" | dd of="$BACKUP_PATH/$SNAPNAME.xva"

#if export was unsuccessful, return error
if [ $? -ne 0 ]; then
echo "Failed to export snapshot name = $snapshot_name$backup_ext"

#calculate backup time, print results
after="$(date +%s)"
elapsed=`bc -l <<< "$after-$before"`
elapsedMin=`bc -l <<< "$elapsed/60"`
echo "Snapshot of $VMNAME saved to $SNAPNAME.xva"
echo "Backup completed in `echo $(printf %.2f $elapsedMin)` minutes"

# destroy snapshot
remote_exec "xe snapshot-uninstall force=true snapshot-uuid=$SNAPUUID"

#remove old backups (uses num_backups variable from top)
BACKUP_COUNT=$(find $BACKUP_PATH -name "$VMNAME*.xva" | wc -l)

if [[ "$BACKUP_COUNT" -gt "$NUM_BACKUPS" ]]; then

OLDEST_BACKUP=$(find $BACKUP_PATH -name "$VMNAME*" -print0 | xargs -0 ls -tr | head -n 1)
echo "Removing oldest backup: $OLDEST_BACKUP"
if [ $? -ne 0 ]; then
echo "Failed to remove $OLDEST_BACKUP"
echo "======================================================"

end=$"$(date +%s)"
total_time=`bc -l <<< "$end-$begin"`
total_time_min=`bc -l <<< "$total_time/60"`
echo "Backup completed: `date`"
echo "VM Backup completed in `echo $(printf %.2f $total_time_min)` minutes"

#Run the backup function and save all output to a variable, including stderr
BACKUP_OUTPUT=$(backup 2>&1)

#Clean up the output of the backup function
#Remove records count from dd, do some basic math to make dd's numbers more human readable
BACKUP_OUTPUT_HUMANIZED=$(echo "$BACKUP_OUTPUT" | sed -r '/.*records /d' | tr -d '()' \
| awk '{sub(/.*bytes /, $1/1024/1024/1024" GB "); sub(/in .* secs/, "in "$5/60" mins "); sub(/mins .*/, "mins (" $7/1024/1024" MB/sec)"); print}')

#Send a report e-mail with the backup results

exit $ret_code