HFS Code42 Cloud Backup: FAQ

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1.1 Who can use the HFS Code42 cloud backup service ?

The service is open to University staff, senior members, academic visitors and postgraduates with a valid Single Sign-On (SSO) account. The service is not currently available to undergraduates or retired staff. Existing users who retire and who wish to continue using the service to backup University data, should ask their local administrator to grant them Academic Visitor status.

1.2 Is every desktop / laptop machine a suitable candidate for the Code42 solution ?

No, not every machine will be able to use the Code42 cloud backup service. The three main prerequisites are as follows:

  • The person responsible for the machine has the status of University staff, senior member, academic visitor or postgraduate, and has a valid Single Sign-On (SSO) account.
  • The machine is a single-user machine: The data belongs to / has been created by just one user, who is responsible for it and the machine.
  • The machine is running a currently supported version of Windows (Windows 11, 10 and 8.1), macOS (Mojave 10.14 and later) and any recent 64-bit Linux distribution using Debian or rpm-based packaging.

1.3 How do I register for the Code42 cloud backup service ?

Download the HFS Hub for your operating platform from the links on the HFS Code42 cloud backup service page. The HFS Hub app will manage your registration with the service, then download and install the correct Code42 app for your machine.

1.4 Can I transfer my backups to another user ? 

Not easily; your backups are linked to your SSO and cannot be simply transferred to another user (SSO) without freshly backing it up again. There are two general solutions listed below:

If you wish to transfer your data (but not the computer) to another user, then the recipient needs to install the Code42 app via the HFS Hub on another device with enough free storage to host that data. Once installed, both you and the recipient need to contact the HFS team and ask them to restore your backups to the recipient's machine. The HFS team can be contacted at hfs@ox.ac.uk. Of course, you don't need Code42 to do this, you can more directly copy data to a standalone USB drive or other storage device to the same effect. Doing this using Code42 does, however,  allow the data to be transferred where for example it no longer resides on your local machine, or is otherwise inaccessible. It also allows the transfer of historical versions of the data, where required.

If you wish to hand a computer, and its backups, back to a department or research group or other user, then the process is as follows:

  • If the new owner is already a user of Code42, then the current machine needs to be deauthorised. To do this the current user needs to start the Code42 app and either double-click the Code 42 logo or press the keys Ctrl Shift and C simultaneously. In the window that appears, type deauthorize and hit return. If this doesn't work, then ask the HFS team to do this. Once done, the new user can sign in to the Code42 app on the machine in question and back it up anew. Note that the data does need to be backed up afresh, as it 'belongs' to a user account. Once done, the new owner should ask the HFS to deactivate the old user's account, and thereby free a user licence for reuse.
  • If the new owner is not already a user of Code42, then they will not immediately be able to sign in to Code42 on the existing machine, since they are not yet a registered user of Code42.  The easiest course of action is to run the HFS Hub and use it to uninstall and then reinstall Code42. The new owner will be registered for use of Code42 as part of this reinstall process. Then the data may be backed up anew to the new owner's new backup account by running a fresh backup (run backup now).

In both cases above, the process may occasionally fail with the symptom being the new user can authenticate via Oxford SSO login page, but the authentication is not passed back to the Code42 app. The app then displays a message 'Unable to login'. In this case, the .identity file (that is a dot preceding the text identity) should be deleted before retrying the login process again. The location of this .identity file is platform specific and can be found from this link under the 'Code42 app file structure' section.

1.5 What happens when I leave the University ?

You will lose access to your backups once your SSO login has expired. Soon after (but not immediately), your backups and account with the Code42 service will be deleted in order to release the user licence for reuse. For these reasons it is advisable to plan what you want to do with your backup data well in advance of leaving. Advice on how to ensure the transfer of data and/or the backup of a machine can be found in the item 1.4 above. 

1.6 What happens if I stop backing up ?

Hopefully this won't happen as the Code42 app should continue to backup your selected files automatically in the background. You can check the status of your backups to the Code42 cloud via the HFS Portal. It is likely that local IT Support will in the future also be provided with reports listing the currency of their supported users' backups.

1.7 How do I update the Code42 software ?

The Code42 app software automatically and silently upgrades itself when updates are released by Code42 and the HFS Team. 

1.8 Do I need to use Oxford University VPN to backup to Code42 ?

No. Unlike the current desktop backup service, the HFS Code42 cloud backup service is accessible from anywhere with an internet connection, thus you can backup over your home broadband connection just as you would over the University network. Bear in mind though that your home broadband may offer a considerably reduced upload bandwidth compared to your download so initial backup speeds may be slow. Using VPN to backup to the HFS Code42 cloud backup service may considerably slow down your backups as it too has restricted bandwidth, shared amongst multiple users. 

1.9 What happens, if I cannot use the Code42 service for one or other of my machines ?

Your machine(s) will remain on the current onsite backup service using the IBM Spectrum Protect software. When the upgraded onsite service is in production, you will be asked to transfer your account(s) to this service. The Spectrum Protect software will be the same, but you will likely be asked to install a newer version of the Spectrum Protect client, and the installation process will be managed by the HFS Hub application.

1.10 Can I use the Code42 service through a firewall?

You can use the Code42 app from anywhere in the world - you do not, for example, need to run it over a VPN. If your machine is behind a firewall and is unable to connect to the Code42 server, then please check with your local IT support that ports 443, 4285 and 4287 are open. It is unlikely that specific IP addresses needed to access Code42 cloud storage will be blocked, but for completeness, these are listed on the Code42 reference page that details IP addresses and ports used by the Code42 platform. For reference, the Oxford University implementation of Code42 signs into the Code42 console at clients.eu5.cpg.crashplan.com.

1.11 I get an error 'hfshub-x64.msi was blocked because it could harm your device' when I download the HFS Hub.

This is due to Windows Smartscreen Defender being a little over-zealous in flagging the HFS Hub download as a potential threat, due to it not having been downloaded enough times and thereby not having won enough 'trust' as a bona-fide download. If you have downloaded the HFS Hub from HFS Code42 Cloud Backup page, then you can be confident that the download is a valid one.

If you wish to further verify the validity of the download, visit this HFS Portal page to determine the md5sum of the download and compare it against that of the downloaded file on your Windows system (open the Command prompt, cd to where the file is downloaded and run certutil -hashfile filename MD5  (where filename is for example hfshub-x64.msi) and compare the output with that listed on the above HFS Portal link).

To proceed to run the file (and thereby install the HFS Hub) do the following:

  1. first move the mouse cursor over the above message, click the three dots that appear, from the dropdown menu and choose 'Keep'.
  2. from the next screen click 'Show more v' and then click 'Keep anyway'.

You will now be able to open the file and run it. On doing so, Windows Defender Smartscreen may display a further warning window: choose 'More info', verify that the publisher is University of Oxford and then click the 'Run anyway' button.

2.1 Is it Crashplan or Code42 ?

Both. The company Code42 originally marketed their product as Crashplan but have recently rebranded it as Code42. Specifically Oxford University IT Services has a subscription to the 'Code42 for Enterprise' product although in practice there are only minor differences between this and other Code42 backup offerings.

2.2 How does Code42 backup work ?

The Code42 app constantly tracks changes (new files and edits to existing files) within your file backup selection and constructs what is essentially a 'to-do' list. Periodically (every 15 minutes by default) it then processes this to-do list for backup to the Oxford tenancy in the Code42 cloud (and any other backup destination you may have locally defined). This process involves deduplication, compression and encryption for secure and efficient transmission and storage of your backup data. The process is more fully described on the Code42 support page entitled how Code42 backup works.

2.3 The Code42 backup is intrusive while I am working on my computer.

The Code42 client app offers several ways of managing your backups so that they do not affect your work and other applications running on your computer. If your machine is running several applications or simply just short of CPU, then you may find the Code42 background backup slows other work and processes down unacceptably. In this case you can manage Code42 backups with limited resources. If you have limited network bandwidth, for example your local broadband connection has a poor/restricted upload bandwidth, then you can manage Code42's bandwidth consumption

2.4 Can I use Code42 to back up a large amount of data ?

The use of Code42 is essentially limited by the resources available to your local computer; CPU and network bandwidth are addressed in the item 2.3 above. Memory is the other critical resource. All Oxford Code42 clients will be version 8 and above, which means that the Code42 app by default will dynamically consume up to a maximum of 25% of the total memory available to your machine. As a rule of thumb Code42 advise that the app will require 1GB of memory for every 1TB of data or 1 million files. If your backup requirements are large, or the Code42 app is crashing on your machine due to insufficient memory, you can adjust the memory settings for the Code42 app.

2.5 Are there any size limits to using Code42 backup ?

Code42 advise that while there are some fixed limits to the amount of backup they will support, these will be preceded by practical limits of how usable the Code42 backup app becomes. Generally, Code42 advise that once an archive approaches the 5-10 TB level, processes such as maintenance (a backend process that manages the integrity of your backups and ensures they are stored efficiently) will start to take a considerable amount of time, during which your backups will be unavailable. Restores will also begin to take considerably longer. When this actually starts to occur, it will depend in part on the structure of your data; the above practical limits will start to be met sooner where the archive consists of many, very small files than with a relatively small number of very large files. 

2.6 Can I back up to another destination other than the cloud ?

Yes, Code42 recommends that users back up to multiple destinations, for example to both the cloud and a local backup destination such as external USB drive, to add resilience and flexibility to your backup strategy. 

2.6 Can I back up files to different destinations with different settings ?

Yes, Code42 employs the concept of backup sets that allow you to do this.

2.7 Can I backup network file shares ?

On Mac and Linux platforms, network file shares can be backed up, so long as they are locally mounted i.e. they are listed as a local Volume or Filesystem on the machine. Network file shares cannot be included for backup on Windows, due to a limitation with the Windows operating system.

2.8 Code42 asks me for a password but doesn't accept it.

This used to occasionally happen when there were problems with registering for the Code42 service but this no longer applies. If this still happens, use the HFS Hub to uninstall the Code42 app. Next, if the HFS Hub app itself is advising an update is available, then click the link to update. Finally, rerun the HFS Hub app and use it to install Code42 anew, following the instructions as they appear. At the end of the installation you should be taken to the familiar University SSO login page to enter your SSO login details. Thereafter, the Code42 app should not prompt you for a password, but rather hand you over to the University SSO login page.

This may also happen when someone is attempting to take responsibility for the backup of a machine previously registered by someone else. This use case and solution is described by FAQ item 1.4 above.

If problems persist, then please contact the HFS team via hfs@it.ox.ac.uk with details of the problem.

2.9 Why are some files and folders excluded and how do I back them up ?

Some files and folders are excluded by Code42 by default. These are indicated in the window used for selecting files and folders for backup by a small red circle to the right; hovering your mouse over the circle should confirm this. There are several reasons for these exclusions:

  • The items excluded are a sensible selection of system, library and temporary files that most users would not usually edit and require a backup.
  • Temporary files, such as cache files are, by their nature temporary and unlikely to be required for the future operation of the machine. As they are constantly changing, they would inflate the amount of data included in the regular, background backup 
  • Including system and library files would, as above, inflate the amount of backup from each machine and the time taken to scan the filesystem for changes, potentially making the Code42 app less usable.

Where you do have edits and data that you are sure you want to include in your backup, then we recommend copying that data to your user area and selecting it for inclusion. You may of course wish to automate or otherwise script this process, where multiple changes take place.

2.10 How do I check my Code42 backups are working ?

  1. Go to the HFS Portal and from the home page click the panel 'My Code42 account'. This will give you a summary of all your machines backing up to the Code42 cloud, and will display links for further details on individual machines.
  2. Open the Code42 app, choose the 'Restore Files' button, select the machine in question and then view and select files and folders you wish to inspect. More details on how to restore files can be found in the Restore section on the getting started with Code42 page and also via Code42 support pages, for example restoring files using the Code42 app .

2.11 Can I install the Code42 app on a headless setup ?

No. Installing the Code42 app on a headless setup is not supported. (as per this Code42 FAQ item)

2.12 How can I backup files outside the standard 'user' area on my computer ?

By default the Code42 app will display the contents of the user area on your machine, as this is where it expects user files to live. If you want to include files outside this area, then choose the 'Manage Files' button and click on the left-most item in the path displayed under the 'Manage Files' text, as highlighted in red in the screenshot below. 

How to navigate up the default path to select files in Code42

In the above example, clicking the highlighted link in blue would allow you to select drives other than the C: drive and select files and folders on those other drives.

2.13 The Code42 backup is very slow. How can I speed it up ?

This predominantly affects the initial backup of a machine, as this usually represents the largest volume of data to be secured in one go. Please refer to the Code42 support page how to speed up your backup for a number of steps you can take and note the following below:

  1. The Oxford default settings are 80% CPU (away) and 20% CPU (present). Remember that these figures represent the percentage of processor time that Code42 can use up to 100% of the processing capacity. Amending the default settings may make sense for your initial backup and any subsequent large backup, depending on how intrusive the backup is on other work your machine is doing, but the default values are likely to be optimal for the frequent small incremental backups of just changed files that will occur once your initial, large backup is complete.
  2. Linux users cannot amend CPU consumption in the Code42 app. Please see the following FAQ item 2.14 below on how to do this.
  3. The default backup frequency setting is every 15 minutes. For initial, and subsequent large, backups, this setting may be counter-productive and, as the article suggests, may benefit from being set to every several hours. Set the versioning for the first week to match the frequency setting (i.e. in the article both frequency and versions are set to every 8 hours). Once the initial and/or large backup is complete, consider reverting to the default settings (backup every 15 minutes and keep a version every 15 minutes for the first week). The golden rule is that the frequency interval should be long enough for the regular backups to complete. If you regularly download or create large files or datasets, it may be that 15 minutes is insufficient to complete the backup of these, in which case the frequency setting and first week versioning should be lengthened accordingly.
  4. If a large backup is to run unattended, be sure to turn off any energy saving settings on your machine as per the Code42 Support item optimize energy settings and the relevant links from that page.
  5. If you have restricted network bandwidth, manage any possible contention by running your backups when the network is likely to be less busy, for example overnight. You can schedule backups to occur within a certain window by opening the app, go to Settings and select the 'Backup Sets' tab and change the Backup Schedule setting (which defaults to always run 24/7). If you schedule backups to run overnight, remember to edit your energy settings as in the above item so that the machine does not sleep, hibernate or power off when unattended.
  6. If you have a large amount of data to backup, consider staging it into 'chunks', based perhaps on priority, importance, value or other criteria of your choosing, and let the backup of each 'chunk' complete before adding a subsequent set of data to your backup set.

2.14 How do I set CPU consumption settings using the Linux Code42 app ?

Curiously the Code42 app for Linux does not provide a means to set CPU resource consumption as it does for Mac and Windows. Thus the below route to amending these is a little convoluted:

Start the Code42 app, go to Settings, select the General tab and click the 'Manage account on the web' link in the bottom right corner. This will open the web client in your default browser and you will need to sign in using your usual SSO credentials (i.e. user1234@OX.AC.UK). 

The web console should open and display a summary status of each of your devices. Click the device name in question to open a window displaying more details of the status and settings for that device. Click the settings button as highlighted in red in the image below and choose the Edit function.

Code42 web console edit device settings

In the resultant Device Backup Settings window, select the General tab, edit the CPU consumption settings as appropriate and Save. Now use the browser back button to return to the device summary page to choose another device, or click the person icon in the top right corner to logout.

Remember that the CPU percentage figures refer to the amount of processor time that the Code42 app can access any amount of CPU capacity up to and including 100% capacity.

2.15 The Code42 app front screen sometimes reports that I have no files backed up and no files selected.

This is an artefact of a process called 'file verification scanning' being run by the Code42 app. This is essentially a second method by which the app ensures that all new, changed and deleted files in your selected areas for backup are reflected in the cloud backup store (the Code42 site provides a fuller explanation). This process runs once a week at 12:00 (noon) by default and can temporarily report zero bytes backed up and zero files selected for backup, if you access the Code42 app while the scan is taking place. For most moderately sized backups, the scan should only take a couple of minutes. If you have a very large amount of data backed up (more than 1TB), then the scan may take longer. Nevertheless, the misreporting of these figures should be temporary.

2.16 The estimated time to completion for my initial backup is ridiculously long. Can I speed it up ?

If you have a large amount of data to backup initially, at least 1TB or more, then it may speed up the initial backup by setting the 'file verification scanning' interval to a period long enough for the backup to complete. You can change the default file verification setting on the Code42 web console, but please remember to change this setting back once you have completed your initial backup. Alternatively you may request this change by contacting the HFS Team (hfs@ox.ac.uk). If your initial backup continues to proceed unacceptably slowly, please refer to item 2.13 above for further help.

2.17 macOS not backing up files with personal data.

Due to Apple's privacy restrictions for files and folders containing personal data in macOS Mojave 10.14 and higher, Code42 cannot back up files from locations like the Desktop, Documents, Downloads, Contacts, Photos, and Mail until you grant access to the Code42 app. A warning message shown below might appear when starting the Code42 app:

screenshot from 2021 10 29 12 20 05

As per the warning message, click the link (also here macOS_not_backing_up_files_with_personal_data) for instructions on how to allow full disk access for the Code42 app in order to backup files with what Apple considers to contain personal content within. The above warning should then no longer display.

If you decide not to allow Code42 access to backup your personal data, and do not want this warning message to display each time, then select the 'Do not show this warning again' checkbox to prevent the warning from appearing the next time you open the Code42 app. 

2.18 Does the Code42 app perform any virus or malware scanning ?

No. Recommended practice is to have anti-virus software installed and up to date on all of your devices. The University provides Sophos Endpoint Agent for this purpose. Contact your local IT Support, if you do not have access to this software.

2.19 Can Code42 help recover from viruses and/or malware infection ?

Yes, but as above, Code42 does no virus or malware scanning itself. It can help recovery from such a situation through the multiple versioning of files it holds in its backup store, thus allowing you to restore versions of files backed up prior to the point of infection and corruption. However, a prerequisite step to restoring your data in this situation is to ensure that you have a 'clean' system to restore to; thus you will need to have installed an up to date copy of anti-virus software on your machine before you restore any files back to it. This applies equally, if you are restoring your data back to a new, replacement machine. A simple step by step guide on both of these scenarios can be found on the Code42 support site from this link: Recovering from viruses and malware.

3.1 Is my data encrypted with Code42 ?

Yes, the data you back up to the Code42 cloud is encrypted both in transit on its way to its destination and at rest in cloud storage using AES256 ciphers. The key is unique to each user and is maintained on each user's computer to encrypt data before sending it to cloud storage, and of course to decrypt data being restored. The key is only readable by the Code42 app on the user device and is automatically removed when either the user or the user device (computer) is deauthorised via the admin console.

A copy of the encryption key is also kept in the Code42 keystore for limited use cases: for web-based restore, when a user is replacing an old computer with a new one and wishes to restore the data to it, and when a user asks an administrator to initiate a 'push' restore to another device / computer. In all cases the key remains private to the user and Code42 has no visibility of it, nor the means to gain visibility. For further information on this topic see how Code42 handles your encryption keys.

3.2 What data does Code42 hold about me ?

Code42 only knows your username (SSO login) and your name. It does not hold your email address, which is held by the HFS within the HFS Portal, or any other information about you.

3.3 Is Code42 suitable for backing up confidential data ?

Yes. The University classifies data under three categories ; public, internal (University) data and Confidential and Code42 has been cleared by the IT services Information Security team for storing all three types. Where you have specific concerns or are handling data of particular sensitivity there may be separate restrictions on how and where this data can be stored. In such cases you are advised to consult with your PI / supervisor, your funding body or the Information Security Team. For reference the University’s data is stored in Code42 datacentres in the EEA.

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