Merge branch 'how-to-org-qubes'

This commit is contained in:
Andrew David Wong 2022-10-28 12:02:42 -07:00
commit 8f0f563f7d
No known key found for this signature in database
GPG Key ID: 8CE137352A019A17
4 changed files with 551 additions and 5 deletions

View File

@ -433,6 +433,10 @@ Some users have been able to do this, but it is neither recommended nor supporte
Qubes should be installed bare-metal.
(After all, it uses its own bare-metal hypervisor!)
### How many qubes should I have? What's a good way to organize them?
[How to organize your qubes](/doc/how-to-organize-your-qubes/) walks through several examples of how different types of users can set up their Qubes OS system to support their unique use cases.
### What is a terminal?
A [terminal emulator](https://en.wikipedia.org/wiki/Terminal_emulator), nowadays often referred to as just a *terminal*, is a program which provides a text window.

View File

@ -13,7 +13,8 @@ title: Getting started
---
After [downloading](/downloads/) and [installing](/doc/installation-guide/)
Qubes OS, it's time to dive in and get to work!
Qubes OS, it's time to dive in and get to work! (Already know your way around?
Dive right in to [organizing your qubes](/doc/how-to-organize-your-qubes/).)
## The Basics
@ -199,10 +200,10 @@ you want to partition some part of your life, you can easily create a new qube
for it. You'll also be able to easily [copy any
files](/doc/how-to-copy-and-move-files) you need to the newly-created qube.
Still not sure? You might find it helpful to read [this
article](https://blog.invisiblethings.org/2011/03/13/partitioning-my-digital-life-into.html),
which describes how one of the Qubes OS architects partitioned her digital life
into security domains.
Want to see some examples? Check out our in-depth guide on [how to organize your
qubes](/doc/how-to-organize-your-qubes/), which walks through several common use
cases based on our user research and years of experience from veteran Qubes
users.
## Secure Habits
@ -221,6 +222,7 @@ Here are some basic tasks you're likely to want to perform often that are
unique to Qubes as a multi-environment system. A full list is available in the
[How-To Guides](/doc/#how-to-guides) section in the docs.
- [How to organize your qubes](/doc/how-to-organize-your-qubes/)
- [How to Update](/doc/how-to-update/)
- [How to Back Up, Restore, and Migrate](/doc/how-to-back-up-restore-and-migrate/)
- [How to Copy and Paste Text](/doc/how-to-copy-and-paste-text/)

View File

@ -248,6 +248,8 @@ title: Introduction
own mistakes. It's a place where you can click on links, open attachments,
plug in devices, and install software free from worry. It's a place where
<em>you</em> have control over your software, not the other way around.
(See some <a href="/doc/how-to-organize-your-qubes/">examples of how
different types of users organize their qubes</a>.)
</p>
<p>
Qubes is also powerful. Organizations like the <a

View File

@ -0,0 +1,538 @@
---
lang: en
layout: doc
permalink: /doc/how-to-organize-your-qubes/
title: How to organize your qubes
---
When people first learn about Qubes OS, their first reaction is often, "Wow,
this looks really cool! But... what can I actually *do* with it?" It's not
always obvious which qubes you should create, what you should do in each one,
and whether your organizational ideas makes sense from a security or usage
perspective.
Each qube is essentially a secure compartment, and you can create as many of
them as you like and connect them to each other in various ways. They're sort
of like Lego blocks in the sense that you can build whatever you want. But if
you're not sure what to build, then this open-ended freedom can be daunting.
It's a bit like staring at a blank document when you first sit down to write
something. The possibilities are endless, and you may not know where to begin!
The truth is that no one else can tell you *exactly* how you should organize
your qubes, as there is no single correct answer to that question. It depends
on your needs, desires, and preferences. Every user's optimal setup will be
different. However, what we *can* do is provide you with some illustrative
examples based on questionnaires and interviews with Qubes users and
developers, as well as our own personal experience and insight from using Qubes
over the years. You may be able to adapt some of these examples to fit your own
unique situation. More importantly, walking you through the rationale behind
various decisions will teach you how to apply the same thought process to your
own organizational decisions. Let's begin!
## Alice, the software developer
Alice is a freelance dev who works on several projects for different clients
simultaneously. The projects have varying requirements and often different
build environments. She has a separate set of qubes for each project. She keeps
them organized by coming up with a naming scheme, such as:
```
clientA-code
clientA-build
clientA-test
clientA-prod
projectB-code
projectB-build-test
projectB-prod
...
```
This helps her keep groups of qubes organized in a set. Some of her qubes are
based on [Debian templates](/doc/templates/debian/), while others are based on
[Fedora templates](/doc/templates/fedora/). The reason for this is that some
software packages are more readily available in one distribution as opposed to
the other. Alice's setup looks like this:
![[Alice's system: diagram 1](/attachment/doc/howto_use_qubes_alice_1.png)](/attachment/doc/howto_use_qubes_alice_1.png)
- **Several qubes for writing code.** Here's where she runs her IDE, commits
code, and signs her commits. These qubes are based on different templates
depending on which tools and which development environment she needs. In
general, Alice likes to have a separate qube of this type for each client or
each project. This allows her to keep everything organized and avoid
accidentally mixing up any access credentials or client code, which could be
disastrous. This also allows her to truthfully tell her clients that their
code is always securely isolated from all her other clients. She likes to use
the [Qubes firewall](/doc/firewall/) to restrict these qubes' network access
to only the code repositories she needs in that qube in order to avoid
accidentally interacting with anything else on her local network or on the
internet. Alice also has some qubes of this type for personal programming
projects that she works on just for fun when she has "free time" (whatever
that is).
- **Several qubes for building and testing.** Again, Alice usually likes to
have one of these for each client or project in order to keep things
organized. However, this can become rather cumbersome and memory-intensive
when many such qubes are running at the same time, so Alice will sometimes
use the same qube for building and testing, or for multiple projects that
require the same environment, when she decides that the marginal benefits of
extra compartmentalization aren't worth the trouble. Here's where she pulls
any dependencies she needs, compiles her code, runs her build toolchain, and
tests her deliverables. In some cases, she finds it useful to use
[standalones](/doc/standalones-and-hvms/) for these so that it's easier to
quickly [install different pieces of software](/doc/how-to-install-software/)
without having to juggle rebooting both the template and an app qube. She
also sometimes finds it necessary (or just convenient) to make edits to
config files in the root filesystem, and she'd rather not have to worry about
losing those changes during an app qube reboot. She knows that she could use
[bind-dirs](/doc/bind-dirs/) to make those changes persistent, but sometimes
she doesn't want to get bogged down doing with all that and figures it
wouldn't be worth it just for this one qube. She's secretly glad that Qubes
OS doesn't judge her this and just gives her the freedom to do things however
she likes while keeping everything securely compartmentalized. At times like
these, she takes comfort in knowing that things can be messy and disorganized
*within* a qube while her overall digital life remains well-organized.
![[Alice's system: diagram 2](/attachment/doc/howto_use_qubes_alice_2.png)](/attachment/doc/howto_use_qubes_alice_2.png)
- **Several email qubes.** Since Alice is a command-line aficionado, she likes
to use a terminal-based email client, so both her work and personal email
qubes are based on a template with
[Mutt](https://github.com/Qubes-Community/Contents/blob/master/docs/configuration/mutt.md)
installed. The email qubes where she sends and receives PGP-signed and
encrypted email securely accesses the private keys in her PGP backend qube
(more on that below). To guard against malicious attachments, she configured
Mutt to open all attachment files in [disposable
qubes](/doc/how-to-use-disposables/).
- **Several qubes for communication tools,** like Signal, Slack, Zoom,
Telegram, IRC, and Discord. This is where she teleconferences and chats with
clients. She uses [USB passthrough](/doc/how-to-use-usb-devices/) to attach
her webcam to each qube as needed and detaches it afterward. Likewise, she
gives each qube access to her microphone while it's needed, then removes
access afterward. This way, she doesn't have to trust any given video chat
program's mute button and doesn't have to worry about being spied on when
she's not on a call. She also has a qube for social media platforms like
Twitter, Reddit, and Hacker News for networking and keeping up with new
developments (or so she claims; in reality, it's mostly for feuds over
programming language superiority, Vim vs. Emacs wars, and tabs vs. spaces
crusades).
- **A GPG backend vault.** Vaults are completely offline qubes that are
isolated from the network. This particular vault holds Alice's private keys
(e.g., for code signing and email) and is securely accessed by several other
"frontend" qubes via the [Split GPG](/doc/split-gpg/) system. Split GPG
allows only the frontend qubes that Alice explicitly authorizes to have the
ability to request PGP operations (e.g., signing and encryption) in the
backend vault. Even then, no qube ever has direct access to Alice's private
keys except the backend vault itself.
- **A password manager vault.** This is another completely offline,
network-isolated qube where Alice uses her offline password manager,
KeePassXC, to store all of her usernames and passwords. She uses the [secure
copy and paste](/doc/how-to-copy-and-paste-text/) system to quickly copy
credentials into other qubes whenever she needs to log into anything.
- **Personal qubes.** One of the things Alice loves the most about Qubes is
that she can use it for both work *and* personal stuff without having to
worry about cross-contamination. Accordingly, she has several qubes that
pertain to her personal life. For example, she has an offline vault that
holds her medical documents, test results, and vaccination records. She has
another offline vault for her government documents, birth certificate, scans
of her passport, and so on. She also has some personal social media accounts
in a separate qube for keeping up with family members and friends from
school.
When she finishes her work for a given client, Alice sends off her
deliverables, [backs up](/doc/how-to-back-up-restore-and-migrate/) the qubes
containing the work for that client, and deletes them from her system. If she
ever needs those qubes again or just wants to reference them, she can easily
restore them from her backup, and the internal state of each one will be
exactly as it was when she finished that project.
## Bob, the investigative journalist
As part of his research and reporting, Bob is frequently forced to interact
with suspicious files, often from anonymous sources. For example, he may
receive an email with an attachment that claims to be a tip about a story he's
working on. Of course, he knows that it could just as easily be malware
intended to infect his computer. Qubes OS is essential for Bob, since it allows
him to handle all this suspicious data securely, keeping it compartmentalized
so that it doesn't risk infecting the rest of his machine.
Bob isn't a super technical guy. He prefers to keep his tools simple so he can
focus on what's important to him: uncovering the truth, exposing the guilty,
exonerating the innocent, and shining light on the dark corners of society. His
mind doesn't naturally gravitate to the technical details of how his computer
works, but he's aware that people are getting hacked all the time and that the
nature of his work might make him a target. He wants to protect his sources,
his colleagues, his family, and himself; and he understands that computer
security is an important part of that. He has a Qubes laptop that he uses only
for work, which contains:
![[A diagram of Bob's system](/attachment/doc/howto_use_qubes_bob.png)](/attachment/doc/howto_use_qubes_bob.png)
- **One offline qube for writing.** It runs only LibreOffice Writer. This is
where Bob does all of his writing. This window is usually open side-by-side
with another window containing research or material from a source.
- **Multiple email qubes.** One is for receiving emails from the general
public. Another is for emailing his editor and colleagues. Both are based on
a [minimal template](/doc/templates/minimal/) with Thunderbird installed.
He's configured both to open all attachments in
[disposables](/doc/how-to-use-disposables/) that are offline in case an
attachment contains a beacon that tries to phone home.
- **Whonix qubes.** He has the standard `sys-whonix` service qube for providing
Torified network access, and he uses disposable `anon-workstation` app qubes
for using Tor Browser to do research on stories he's writing. Since the topic
is often of a sensitive nature and might implicate powerful individuals, it's
important that he be able to conduct this research with a degree of
anonymity. He doesn't want the subjects of his investigation to know that
he's looking into them. He also doesn't want his network requests being
traced back to his work or home IP addresses. Whonix helps with both of these
concerns. He also has another Whonix-based disposable template for receiving
tips anonymously via Tor, since some high-risk whistleblowers he's interacted
with have said that they can't take a chance with any other form of
communication.
- **Two qubes for
[Signal](https://github.com/Qubes-Community/Contents/blob/master/docs/privacy/signal.md).**
Bob has two Signal app qubes (both on the same template in which the Signal
desktop app is installed). One is linked to his own mobile number for
communicating with co-workers and other known, trusted contacts. The other is
a public number that serves as an additional way for sources to reach him
confidentially. This is especially useful for individuals who don't use Tor
but for whom unencrypted communication could be dangerous.
- **Several data vaults.** When someone sends Bob material that turns out to be
useful, or when he comes across useful material while doing his own research,
he stores a copy in a completely offline, network-isolated vault qube. Most
of these files are PDFs and images, though some are audio files, videos, and
text files. Since most of them are from unknown or untrusted sources, Bob
isn't sure if it would be safe to put them all in the same vault, so he makes
different vaults (usually one for each story or topic) just in case. This has
the side benefit of helping to keep things organized.
- **A [VPN
qube](https://github.com/Qubes-Community/Contents/blob/master/docs/configuration/vpn.md)
and associated qubes for accessing work resources.** The servers at work can
only be accessed from the organization's network, so Bob has certain qubes
that are connected to a VPN qube so that he can upload his work and access
anything he needs on the local network when he's not physically there.
- **A password manager vault.** Bob stores all of his login credentials in the
default password manager that came with his offline vault qube. He [securely
copies and pastes](/doc/how-to-copy-and-paste-text/) them into other qubes as
needed.
A colleague helped Bob set up his Qubes system initially and showed him how to
use it. Since Bob's workflow is pretty consistent and straightforward, the way
his qubes are organized doesn't change much, and this is just fine by him. His
colleague told him to remember a few simple rules: Don't copy or move
[text](/doc/how-to-copy-and-paste-text/) or
[files](/doc/how-to-copy-and-move-files/) from less trusted to more trusted
qubes; [update](/doc/how-to-update/) your system when prompted; and make
regular [backups](/doc/how-to-back-up-restore-and-migrate/). Bob doesn't have
the need to try out new software or tweak any settings, so he can do everything
he needs to do on a daily basis without having to interact with the command
line.
## Carol, the investor
Carol works hard and lives below her means so that she can save money and
invest it for her future. She hopes to become financially independent and maybe
even retire early someday, and she's decided that her best bet for achieving
this is by investing for the long term and allow compounding to do its work.
However, after doing some research into her country's consumer financial
protection laws, she learned that there's no legal guarantee that customers
will be made whole in the event of theft or fraud. The various insurance and
protection organizations only guarantee recovery in the case of a financial
institution *failing*, which is quite different from an individual customer
being hacked. Moreover, even though many financial institutions have their own
cybercrime policies, rarely, if ever, do they explicitly guarantee
reimbursement in the event that a *customer* gets hacked (rather than the
institution itself).
<div class="alert alert-warning" role="alert">
<i class="fa fa-exclamation-circle"></i>
Carol looked into how thieves might actually try to steal her hard-earned
wealth and was surprised to learn that they have all sorts of ploys that she
had never even considered. For example, she had assumed that any theft would,
at the bare minimum, have to involve transferring money out of her account.
That seems like a safe assumption. But then she read about "pump and dump"
attacks, where thieves buy up some penny stock, hack into innocent people's
brokerage accounts, then use the victims' funds to buy that same penny stock,
"pumping" up its price so that the thieves can "dump" their shares on the
market, leaving the victims with worthless shares. No money is ever
transferred into or out of the victims' account; it's just used to buy and
sell securities. So, all the safeguards preventing new bank accounts from
being added or requiring extra approval for outbound transfers do nothing to
protect victims' funds in cases like these. And this is just one example!
Carol realized that she couldn't assume that existing safeguards against
specific, known attacks were enough. She had to think about security at a
more fundamental level and design it into her digital life from the ground
up.
</div>
After learning about all this, Carol decided that it was ultimately up to her
to take care of her own cybersecurity. She couldn't rely on anyone else to do
it for her. Sure, most people just use regular consumer tech and will probably
end up fine, but, she reminded herself, most people also don't have as much to
lose. It's not a risk that she was willing to take with her future, especially
knowing that there's probably no government bailout waiting for her and that
all the brokerage firms' vaguely reassuring marketing language about
cybersecurity isn't legally binding. So, Carol started reading more about
computer security and eventually stumbled upon Qubes OS after searching the web
for "most secure operating system." She read about how it's designed and why.
Although she didn't immediately understand all of the technical details, the
fundamental principle of [security-by-compartmentalization](/doc/architecture/)
made intuitive sense to her, and the more she learned about the technical
aspects, the more she realized that this is what she'd been looking for. Today,
her setup looks like this:
![[A diagram of Carol's system](/attachment/doc/howto_use_qubes_carol.png)](/attachment/doc/howto_use_qubes_carol.png)
- **One qube for each investment firm and bank.** Carol has a few different
retirement accounts, brokerage accounts, and bank accounts. She treats each
qube like a "secure terminal" for accessing only that one institution's
website. She makes her transactions and saves any statements and
confirmations she downloads in that qube. She uses the [Qubes
firewall](/doc/firewall/) to enable access only to that institution's website
in that qube so that she doesn't accidentally visit any others. Since most of
what she does involves using websites and PDFs, most of Carol's app qubes are
based on a [minimal template](/doc/templates/minimal/) with just a web
browser (which doubles as a PDF viewer) and a file manager installed.
- **One qube for all her credit card accounts.** Carol started to make a
separate qube for each credit card account but ultimately decided against it.
For one thing, the consumer protections for credit card fraud in her country
are much better than for losing assets to theft or fraud in a bank or
brokerage account, so the security risk isn't as high. Second, there's
actually not a whole lot that an attacker could do with access to her credit
cards' online accounts or her old credit card statements, since online access
to these generally doesn't allow spending or withdrawing any money. So, even
the worst case scenario here wouldn't be catastrophic, unlike with her bank
and brokerage accounts. Third, she's not too worried about any of her credit
card company websites being used to attach each other or her qube (As long as
it's contained to a single qube, she's fine with that level of risk.) Last,
but not least: She has way too many credit cards! While Carol is very frugal,
she likes to collect the sign-up bonuses that are offered for opening new
cards, so she's accumulated quite a few of them. (However, she's always
careful to pay off her balance each month, so she never pays interest. She's
also pretty disciplined about only spending what she would have spent
*anyway* and not being tempted to spend more just to meet a spending
requirement or because she can.) At any rate, Carol has decided that the tiny
benefit she stands to gain from having a separate qube for every credit card
website wouldn't be worth the hassle of having to manage so many extra qubes.
- **A qube for credit monitoring, credit reports, and credit history
services.** Carol has worked hard to build up a good credit score, and she's
concerned about identity theft, so she has one qube dedicated to managing her
free credit monitoring services and downloading her free annual credit
reports.
- **Two qubes for taxes.** Carol has a [Windows
qube](https://github.com/Qubes-Community/Contents/blob/master/docs/os/windows/windows.md)
for running her Windows-only tax software. She also has an offline vault
where she stores all of her tax-related forms and documents, organized by
year.
- **A qube for financial planning and tracking.** Carol loves spreadsheets, so
this offline qube is where she maintains a master spreadsheet to track all of
her investments and her savings rate. She also keeps her budgeting
spreadsheet, insurance spreadsheet, and written investment policy statement
here. This qube is based on a template with some additional productivity
software, like LibreOffice and Gnumeric (so that Carol can run her own Monte
Carlo simulations).
- **Various email qubes.** Carol likes to have one email qube for her most
important financial accounts; a separate one for her credit cards accounts,
online shopping accounts, and insurance companies; and another one for
personal email. They're all based on the same template with Thunderbird
installed.
- **A password manager vault.** A network-isolated qube where Carol stores all
of her account usernames and passwords in KeePassXC. She uses the [Qubes
global clipboard](/doc/how-to-copy-and-paste-text/) to copy and paste them
into her other qubes when she needs to log into her accounts.
## Bonus: Carol explores new financial technology
The vast majority of Carol's assets are in broad-based, low-cost,
passively-managed indexed funds. Lately, however, she's started getting
interested in cryptocurrency. She's still committed to staying the course with
her tried-and-true investments, and she's always been skeptical of new asset
classes, especially those that don't generate cash flows or that often seem to
be associated with scams or wild speculation. However, she finds the ability to
self-custody a portion of her assets appealing from a long-term risk management
perspective, particularly as a hedge against certain types of political risk.
<div class="alert alert-danger" role="alert">
<i class="fa fa-exclamation-triangle"></i>
Some of Carol's friends warned her that cryptocurrency is extremely volatile
and that hacking and theft are common occurrences. Carol agreed and reassured
them that she's educated herself about the risks and will make sure she never
invests more than she can afford to lose.
</div>
Carol has added the following to her Qubes setup:
- **A standalone qube for running Bitcoin Core and an offline wallet vault.**
Carol finds the design and security properties of Bitcoin very interesting,
so she's experimenting with running a full node. She also created a
network-isolated vault in order to try running a copy of Bitcoin Core
completely offline as a "cold storage" wallet. She's still trying to figure
out how this compares to an actual hardware wallet, paper wallet, or
physically air-gapped machine, but she's figures they all have different
security properties. She also recently heard about using [Electrum as a
"split" wallet in
Qubes](https://github.com/Qubes-Community/Contents/blob/master/docs/security/split-bitcoin.md)
and is interested in exploring that further.
- **Whonix qubes.** Carol read somewhere that Bitcoin nodes should be run over
Tor for privacy and security. She found it very convenient that Whonix is
already integrated into Qubes, so she simply set her Bitcoin Core "full node"
qube to use `sys-whonix` as its networking qube.
- **Various qubes for DeFi and web3.** Carol has also started getting into DeFi
(decentralized finance) and web3 on Ethereum and other smart contract
blockchains, so a friend recommended that she get a Ledger hardware wallet.
She downloaded the Ledger Live software in an app qube and [set up her system
to recognize the
Ledger](https://www.kicksecure.com/wiki/Ledger_Hardware_Wallet). She can now
start her [USB qube](/doc/usb-qubes/), plug her Ledger into it into a USB
port, [use the Qubes Devices widget to attach it](/doc/how-to-use-devices/)
to her Ledger Live qube, and from there she can interact with the software.
She has a separate qube with the Metamask extension installed in a web
browser. She can also use the Qubes Devices widget to attach her Ledger to
this qube so she can use Metamask in conjunction with her Ledger to interact
with smart contracts and decentralized exchanges.
- **Various qubes for research and centralized exchanges.** Carol uses these
when she wants to check block explorer websites, coin listing and market cap
sites, aggregation tools, or just to see what the latest buzz is on Crypto
Twitter.
Carol makes sure to back up all of her qubes that contain important account
statements, confirmations, spreadsheets, cryptocurrency wallets, and her
password manager vault. If she has extra storage space, she'll also back up her
templates and even her Bitcoin full node qube, but she'll skip them if she
doesn't have time or space, since she knows she can always recreate them again
later and download what she needs from the Internet.
## Conclusion
The characters we've met today may be fictional, but they represent the needs
of real users like you. You may find that your own needs overlap with more than
one of them, in which case you may find it useful to model certain subsets of
your overall Qubes system on different examples. You probably also noticed that
there are commonalities among them. Most people need to use email, for example,
so most people will need at least one email qube and a suitable template to
base it on. But not everyone will need [Split GPG](/doc/split-gpg/), and not
everyone will want to use the same email client. On the other hand, almost
everyone will need a password manager, and it pretty much always makes sense to
keep it in an offline, network-isolated vault.
<div class="alert alert-info" role="alert">
<i class="fa fa-circle-info"></i>
As you gain experience with Qubes, you may find yourself disagreeing with
some of the decisions our fictional friends made. That's okay! There are many
different ways to organize a Qubes system, and the most important criterion
is that it serves the needs of its owner. Since everyone's needs are
different, it's perfectly normal to find yourself doing things a bit
differently. Nonetheless, there are some general principles that almost all
users find helpful, especially when they're first starting out.
</div>
As you're designing your own Qubes system, keep in mind some of the following
lessons from our case studies:
- **You'll probably change your mind as you go.** You'll realize that one qube
should really be split into two, or you'll realize that it doesn't really
make sense for two qubes to be separate and that they should instead be
merged into one. That's okay. Qubes OS supports your ability to adapt and
make changes as you go. Try to maintain a flexible mindset. Things will
eventually settle down, and you'll find your groove. Changes to the way you
organize your qubes will become less drastic and less frequent over time.
- **[Make frequent backups.](/doc/how-to-back-up-restore-and-migrate/)** Losing
data is never fun, whether it's from an accidental deletion, a system crash,
buggy software, or a hardware failure. By getting into the habit of making
frequent backups now, you'll save yourself from a lot of pain in the future.
Many people never take backups seriously until they suffer catastrophic data
loss. That's human nature. If you've experienced that before, then you know
the pain. Resolve now never to let it happen again. If you've never
experienced it, count yourself lucky and try to learn from the hard-won
experience of others. Keeping good backups also allows you to be a bit more
free with reorganizations. You can delete qubes that you think you won't need
anymore without having to worry that you might need them again someday, since
you know you can always restore them from a backup.
- **Think about which programs you want to run and where you want to store
data.** In some cases, it makes sense to run programs and store data in the
same qube, for example, if the data is generated by that program. In other
cases, it makes sense to have qubes that are exclusively for storing data
(e.g., offline data storage vaults) and other qubes that are exclusively for
running programs (e.g., web browser-only qubes). Remember that when you make
backups, it's only essential to back up data that can't be replaced. This can
allow you to achieve minimal backups that are quite small compared to the
total size of your installation. Templates, service qubes, and qubes that are
used exclusively for running programs and that contain no data don't
necessarily have to be backed up as long as you're confident that you can
recreate them if needed. This is why it's a good practice to keep notes on
which packages you installed in which templates and which customizations and
configurations you made. Then you can refer to your notes the next time you
need to recreate those qubes. Of course, backing up everything is not a bad
idea either. It may require a bit more time and disk space upfront, but for
some people, it can be just as important as backing up their irreplaceable
data. If your system is mission-critical, and you can't afford more than a
certain amount of downtime, then by all means, back everything up!
- **Introspect on your own behavior.** For example, if you find yourself
wanting to find some way to get two qubes to share the same storage space,
then this is probably a sign that those two qubes shouldn't be separate in
the first place. Sharing storage with each other largely breaks down the
secure wall between them, making the separation somewhat pointless. But you
probably had a good reason for wanting to make them two separate qubes
instead of one to begin with. What exactly was that reason? If it has to do
with security, then why are you okay with them freely sharing data that could
allow one to infect the other? If you're sure sharing the data wouldn't cause
one to infect the other, then what's the security rationale for keeping them
separate? By critically examining your own thought process in this way, you
can uncover inconsistencies and contradictions that allow you to better
refine your system, resulting in a more logical organization that serves your
needs better and better over time.
- **Don't assume that just because *you* can't find a way to attack your
system, an adversary wouldn't be able to.** When you're thinking about
whether it's a good idea to combine different activities or data in a single
qube, for example, you might think, "Well, I can't really see how these pose
a risk to each other." The problem is that we often miss attack vectors that
sophisticated adversaries spot and can use against us. After all, most people
don't think that using a conventional monolithic operating system is risky,
when in reality their entire digital life can be taken down in one fell
swoop. That's why a good rule of thumb is: When in doubt, compartmentalize.
- **But remember that compartmentalization --- like everything else --- can be
taken to an extreme.** The appropriate amount depends on your temperament,
time, patience, experience, risk tolerance, and expertise. In short, there
can be such a thing as *too much* compartmentalization! You also have to be
able to actually *use* your computer efficiently to do the things you need to
do. For example, if you immediately try to jump into doing everything in
[disposables](/doc/how-to-use-disposables/) and find yourself constantly
losing working (e.g., because you forget to transfer it out before the
disposable self-destructs), then that's a big problem! Your extra
self-imposed security measures are interfering with the very thing they're
designed to protect. At times like these, take a deep breath and remember
that you've already reaped the vast majority of the security benefit simply
by using Qubes OS in the first place and performing basic
compartmentalization (e.g., no random web browsing in templates). Each
further step of hardening and compartmentalization beyond that represents an
incremental gain with diminishing marginal utility. Try not to allow the
perfect to be the enemy of the good!