commit cc258e468f192b730e24446d77ebe3e7f38cc734 Author: gus gus@torproject.org Date: Thu Jul 4 18:35:29 2019 -0400
Reorganize Relay Operations sections --- .../relay-operations/technical-setup/contents.lr | 444 +-------------------- 1 file changed, 9 insertions(+), 435 deletions(-)
diff --git a/content/relay-operations/technical-setup/contents.lr b/content/relay-operations/technical-setup/contents.lr index 65d44fc..07925c7 100644 --- a/content/relay-operations/technical-setup/contents.lr +++ b/content/relay-operations/technical-setup/contents.lr @@ -4,106 +4,28 @@ section_id: relay-operations --- color: primary --- -key: 3 +key: 4 --- _template: layout.html --- title: Technical setup --- -subtitle: Installing and configuring your Tor relay. +subtitle: Installing and configuring your Tor relay: Bridge, Guard / Middle node, Exit. --- html: two-columns-page.html --- body:
-# Considerations when choosing a hosting provider - -If you have access to a high speed internet connection (>=100 Mbit/s in both directions) and a physical piece of computer hardware, this is the best way to run a relay. -Having full control over the hardware and connection gives you a more controllable and (if done correctly) secure environment. -You can host your own physical hardware at home (do NOT run a Tor exit relay from your home) or in a data center. -Sometimes this is referred to as installing the relay on "bare metal". - -If you do not own physical hardware, you could run a relay on a rented dedicated server or virtual private server (VPS). -This can cost anywhere between $3.00/month and thousands per month, depending on your provider, hardware configuration, and bandwidth usage. -Many VPS providers will not allow you to run exit relays. -You must follow the VPS provider's terms of service, or risk having your account disabled. -For more information on hosting providers and their policies on allowing Tor relays, please see this list maintained by the Tor community: [GoodBadISPs](FIXME). - -## Questions to consider when choosing a hoster - -* How much monthly traffic is included? (Is bandwidth "unmetered"?) -* Does the hoster provide IPv6 connectivity? (it is recommended, but not required) -* What virtualization / hypervisor (if any) does the provider use? (anything but OpenVZ should be fine) -* Does the hoster start to throttle bandwidth after a certain amount of traffic? -* How well connected is the autonomous system of the hoster? To answer this question you can use the AS rank of the autonomous systems if you want to -compare: http://as-rank.caida.org/ (a lower value is better) - -## If you plan to run Exit Relays - -* Does the hoster allow Tor exit relays? (explicitly ask them before starting an exit relay there) -* Does the hoster allow custom WHOIS records for your IP addresses? This helps reduce the amount of abuse sent to the hoster instead of you. -* Does the hoster allow you to set a custom DNS reverse entry? (DNS PTR record) - This are probably things you will need to ask the hoster in a Pre-Sales ticket - -# AS/location diversity - -When selecting your hosting provider, consider network diversity on an autonomous system (AS) and country level. -A more diverse network is more resilient to attacks and outages. -Sometimes it is not clear which AS you are buying from in case of resellers. -To be sure it is best to ask the hoster about the AS number before ordering a server. - -It is best to avoid hosters where many Tor relays are already hosted, but it is still better to add one there than to run no relay at all. - **Try to avoid** the following hosters: - -* OVH SAS (AS16276) -* Online S.a.s. (AS12876) -* Hetzner Online GmbH (AS24940) -* DigitalOcean, LLC (AS14061) - -To find out which hoster and countries are already used by many other operators (that should be avoided) you can use Relay Search: - -* [Autonomous System Level Overview](https://metrics.torproject.org/rs.html#aggregate/as) -* [Country Level Overview](https://metrics.torproject.org/rs.html#aggregate/cc) - -# Choosing an Operating System - -We recommend you use the operating system you are most familiar with. -Please keep in mind that since most relays run on Debian and we want to avoid a monoculture, BSD and other non-Linux based relays are greatly needed. - -The following table shows the current OS distribution on the Tor network to give you an idea of how much more non-Linux relays we should have: - -* https://nusenu.github.io/OrNetStats/#os-distribution-relays - -# OS Level Configuration - -OS configuration is outside the scope of this guide but the following points are crucial for a Tor relay, so we want to mention them here nonetheless. - -## Time Synchronization (NTP) - -Correct time settings are essential for Tor relays. It is recommended that you use the network time protocol (NTP) for time synchronization and ensure your timezone is set correctly. - -## Automatic Software Updates - -One of the most imported things to keeps your relay secure is to install security updates timely and ideally automatically so you can not forget about it. -We collected the steps to enable automatic software updates for different operating systems: - -* [RPM-based distributions](FIXME) (RHEL, CentOS, Fedora, openSUSE) -* [Debian/Ubuntu](FIXME) -* [FreeBSD/HardenedBSD](FIXME) - -# Tor Relay Setup: Installation and Configuration - This section covers the installation and configuration of the program required to run a Tor relay for various operating systems. + These steps are intended for the latest stable version of the given OS, on Ubuntu for the latest LTS release.
Note: For some operating systems, there are alpha version packages available (tor versions with new features not deemed to be stable yet). + These are only recommended for people eager to test and report bugs in bleeding edge releases/features. If you are looking to run a relay with minimal effort we recommend you stick to stable releases.
-In this guide we describe how to setup a new non-exit relay. -By reading further you can easily switch to become an exit relay. - -**Questions you should clarify before configuring Tor:** +# Questions you should clarify before configuring Tor
* Do you want to run a Tor exit or non-exit (guard/middle) relay? * If you want to run an exit relay: Which ports do you want to allow in your exit policy? (more ports usually means potentially more abuse complains) @@ -116,362 +38,14 @@ By reading further you can easily switch to become an exit relay.
The installation commands are shown in code blocks and must be executed with root privileges.
-## Make sure relay ports can be reached - -If you are using a firewall, open a hole in your firewall so incoming connections can reach the ports you will use for your relay (ORPort, plus DirPort if you enabled it). -Also, make sure you allow all outgoing connections too, so your relay can reach the other Tor relays, clients and destinations. -You can find the specific ORPort TCP port number in the torrc configuration samples bellow (in the OS specific sections). - ## Configuration Management
-Tor does not scale well on multi-core machines. -If you run a Tor relay on a server with a fast Internet uplink (>200 Mbit/s) you might want to consider running multiple Tor instances on a single server with multiple cores. -Note: You can only run two tor instances per public IPv4 address. - If you plan to run more than a single relay, or you want to run a high capacity relay (multiple Tor instances per server) or want to use strong security features like [Offline Master Keys](https://trac.torproject.org/projects/tor/wiki/doc/TorRelaySecurity/OfflineKe...) without performing additional steps manually, you may want to use a configuration management for better maintainability.
There are multiple configuration management solutions for Unix based operating systems (Ansible, Puppet, Salt, ...).
-The following Ansible Role has specifically been build for Tor relay operators and supports multiple operating systems: - -http://github.com/nusenu/ansible-relayor - -## Platform specific Instructions - -Please choose your platform: - -* Debian/Ubuntu -* CentOS/RHEL -* Fedora -* FreeBSD -* openSUSE - -## Verify that your relay works - -If your logfile (syslog) contains the following entry after starting your tor daemon your relay should be up and running as expected: - -``` -Self-testing indicates your ORPort is reachable from the outside. Excellent. -Publishing server descriptor. -``` - -About 3 hours after you started your relay it should appear on [Relay Search](https://metrics.torproject.org/rs.html). -You can search for your relay using your nickname or IP address. - -# Getting Help - -If you run into problems while setting up your relay you can ask your questions on the public tor-relays mailing list: - -* https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-relays - -This is a great resource for asking (and answering) questions, and generally getting to know other relay operators. -Make sure to check out the archives! - -# Limiting bandwidth usage (and traffic) - -Tor will not limit its bandwidth usage by default, but supports multiple ways to restrict the used bandwidth and the amount of traffic. -This can be handy if you want to ensure that your Tor relay does not exceed a certain amount of bandwidth or total traffic per day/week/month. -The following torrc configuration options can be used to restrict bandwidth and traffic: - -* AccountingMax -* AccountingRule -* AccountingStart -* BandwidthRate -* BandwidthBurst -* RelayBandwidthRate - -Having a fast relay for some time of the month is preferred over a slow relay for the entire month. - -Also see the bandwidth entry in the FAQ: https://www.torproject.org/docs/faq.html.en#BandwidthShaping - -# IPv6 - -We encourage everyone to enable IPv6 on their relays. This is especially valuable on exit and guard relays. - -Before enabling your tor daemon to use IPv6 in addition to IPv4 you should do some basic IPv6 connectivity tests. - -The following command line will ping the IPv6 addresses of Tor directory authorities from your server: - -``` -ping6 -c2 2001:858:2:2:aabb:0:563b:1526 && ping6 -c2 2620:13:4000:6000::1000:118 && ping6 -c2 2001:67c:289c::9 && ping6 -c2 2001:678:558:1000::244 && ping6 -c2 2607:8500:154::3 && ping6 -c2 2001:638:a000:4140::ffff:189 && echo OK. -``` - -At the end of the output you should see "OK." if that is not the case do not enable IPv6 in your torrc configuration file before IPv6 is indeed working. -If you enable IPv6 without working IPv6 connectivity your entire relay will not be used, regardless if IPv4 is working. - -If it worked fine, make your Tor relay reachable via IPv6 by adding an additional ORPort line to your configuration (example for ORPort 9001): - -``` -ORPort [IPv6-address]:9001 -``` - -The location of that line in the configuration file does not matter you can simply add it next to the first ORPort lins in your torrc file. - -Note: You have to explicitly specify your IPv6 address in square brackets, you can not tell tor to bind to any IPv6 (like you do for IPv4). -If you have a global IPv6 address you should be able to find it in the output of the following command: - -``` -ip addr|grep inet6|grep global -``` - -If you are an exit relay with IPv6 connectivity, tell your tor daemon to allow exiting via IPv6 so clients can reach IPv6 destinations: - -``` -IPv6Exit 1 -``` - -Note: Tor requires IPv4 connectivity, you can not run a Tor relay on IPv6-only. - -# Important if you run more than one Tor instance - -To avoid putting Tor clients at risk when operating multiple relays you must set a proper [MyFamily](https://2019.www.torproject.org/docs/tor-manual.html.en#MyFamily) value and have a valid [ContactInfo](https://2019.www.torproject.org/docs/tor-manual.html.en#ContactInfo) in your torrc configuration. -The MyFamily setting is simply telling Tor clients what Tor relays are controlled by a single entity/operator/organization, so they are not used in multiple positions in a single circuit. - -If you run two relays and they have fingerprints AAAAAAAAAA and BBBBBBBB, you would add the following configuration to set MyFamily: - -``` -MyFamily AAAAAAAAAA,BBBBBBBB -``` - -to both relays. To find your relays fingerprint you can look into the log files when tor starts up or find the file named "fingerprint" in your tor DataDirectory. - -Instead of doing so manually for big operators we recommend to automate the MyFamily setting via a configuration management solution. -Manually managing MyFamily for big relaygroups is error prone and can put Tor clients at risk. - -# Exit Relay Configuration - -It is recommended that you setup exit relays on servers dedicated to this purpose. It is not recommended to install Tor exit relays on servers that you need for other services as well. -Do not mix your own traffic with your exit relay traffic. - -## Reverse DNS and WHOIS record - -Before switching your relay to become an exit relay, ensure that you have set a clear DNS reverse (PTR) record to make it clear for everyone that this is a tor exit relay. -Something like "tor-exit" it its name is a good start. - -If your provider offers it, make sure your WHOIS record contains clear indications that this is a Tor exit relay. - -## Exit Notice HTML page +The following Ansible Role has specifically been build for Tor relay operators and supports multiple operating systems: [Ansible Relayor](http://github.com/nusenu/ansible-relayor).
-To make it even more obvious that this is a Tor exit relay you should serve a Tor exit notice HTML page. -Tor can do that for you if your DirPort is on TCP port 80, you can make use of tor's DirPortFrontPage feature to display a HTML file on that port. -This file will be shown to anyone directing his browser to your Tor exit relay IP address. - -``` -DirPort 80 -DirPortFrontPage /path/to/html/file -``` - -We offer a sample Tor exit notice HTML file, but you might want to adjust it to your needs: -https://gitweb.torproject.org/tor.git/plain/contrib/operator-tools/tor-exit-... - -Here are some more tips for running a reliable exit relay: -https://blog.torproject.org/tips-running-exit-node - -## Exit Policy - -Defining the [exit policy](https://www.torproject.org/docs/tor-manual.html.en#ExitPolicy) is one of the most important parts of an exit relay configuration. -The exit policy defines which destination ports you are willing to forward. -This has an impact on the amount of abuse emails you will get (less ports means less abuse emails, but an exit relay allowing only few ports is also less useful). -If you want to be a useful exit relay you must **at least allow destination ports 80 and 443**. - -As a new exit relay - especially if you are new to your hoster - it is good to start with a reduced exit policy (to reduce the amount of abuse emails) and further open it up as you become more experienced. -The reduced exit policy can be found on the [ReducedExitPolicy](https://trac.torproject.org/projects/tor/wiki/doc/ReducedExitPolicy) wiki page. - -To become an exit relay change ExitRelay from 0 to 1 in your torrc configuration file and restart the tor daemon. - -``` -ExitRelay 1 -``` - -## DNS on Exit Relays - -Unlike other types of relays, exit relays also do DNS resolution for Tor clients. -DNS resolution on exit relays is crucial for Tor clients, it should be reliable and fast by using caching. - -* DNS resolution can have a significant impact on the performance and reliability your exit relay provides. Poor DNS performance will result in less traffic going through your exit relay. -* Don't use any of the big DNS resolvers as your primary or fallback DNS resolver to avoid centralization (Google, OpenDNS, Quad9, Cloudflare, 4.2.2.1-6) -* We recommend running a local caching and DNSSEC-validating resolver without using any forwarders (specific instructions follow bellow for each operating systems) -* if you want to add a second DNS resolver as a fallback to your /etc/resolv.conf configuration, try to choose a resolver within your autonomous system and make sure it is not your first entry in that file (the first entry should be your local resolver) -* if a local resolver like unbound is not an option for you try to use a resolver that your provider runs in the same autonomous system (to find out if an IP address is in the same AS as your relay, you can look it up, using for example https://bgp.he.net). -* try to avoid adding too many resolvers to your /etc/resolv.conf file to limit exposure on an AS-level (try to not use more than two entries) - -There are multiple options for DNS server software, unbound has become a popular one but **feel free to use any other you are comfortable with**. -When choosing your DNS resolver software try to ensure it supports DNSSEC validation and QNAME minimisation (RFC7816). -In every case the software should be installed using the OS package manager to ensure it is updated with the rest of the system. - -By using your own DNS resolver you are less vulnerable to DNS-based censorship that your upstream resolver might impose. - -Here follow specific instructions on how to install and configure unbound on your exit - a DNSSEC-validating and caching resolver. unbound has many configuration and tuning nobs but we try to keep these instructions as simple and short as possible and the basic setup will do just fine for most operators. - -After switching to unbound verify it works as expected by resolving a valid hostname, if it does not work, you can restore the old resolv.conf file. - -### Debian/Ubuntu - -The following 3 commands install unbound, backup your DNS configuration and tell the system to use the local unbound: - -``` -apt install unbound -cp /etc/resolv.conf /etc/resolv.conf.backup -echo nameserver 127.0.0.1 > /etc/resolv.conf -``` - -To avoid that the configuration gets changed (for example by the DHCP client): - -``` -chattr +i /etc/resolv.conf -``` - -The Debian configuration ships with QNAME minimisation (RFC7816) enabled by default so you don't need to enable it explicitly. -The unbound resolver you just installed does also DNSSEC validation. - -### CentOS/RHEL - -Install the unbound package: - -``` -yum install unbound -``` - -in /etc/unbound/unbound.conf replace the line - -``` -# qname-minimisation: no -``` - -with: - -``` -qname-minimisation: yes -``` - -enable and start unbound: - -``` -systemctl enable unbound -systemctl start unbound -``` - -Tell the system to use the local unbound server: - -``` -cp /etc/resolv.conf /etc/resolv.conf.backup -echo nameserver 127.0.0.1 > /etc/resolv.conf -``` - -To avoid that the configuration gets changed (for example by the DHCP client): - -``` -chattr +i /etc/resolv.conf -``` - -### FreeBSD - -FreeBSD ships unbound in the base system but the one in ports is usually following upstream more closely so we install the unbound package: - -``` -pkg install unbound -``` - -Replace the content in /usr/local/etc/unbound/unbound.conf with the following lines: - -``` -server: - verbosity: 1 - qname-minimisation: yes -``` - -enable and start the unbound service: - -``` -sysrc unbound_enable=YES -service unbound start -``` - -Tell the system to use the local unbound server: - -``` -cp /etc/resolv.conf /etc/resolv.conf.backup -echo nameserver 127.0.0.1 > /etc/resolv.conf -``` - -To avoid that the configuration gets changed (for example by the DHCP client): - -``` -chflags schg /etc/resolv.conf -``` - -# Tor relay lifecycle - -It takes some time for relay traffic to ramp up, this is especially true for guard relays but to a lesser extend also for exit relays. -To understand this process, read about the lifecycle of a new relay: -https://blog.torproject.org/lifecycle-new-relay - -# Maintaining a relay - -## Backup Tor Identity Keys - -After your initial installation and start of the tor daemon it is a good idea to make a backup of your relay's long term identity keys. -They are located in the "keys" subfolder of your DataDirectory (simply make a copy of the entire folder and store it in a secure location). -Since relays have a ramp-up time it makes sense to backup the identity key to be able to restore your relay's reputation after a disk failure - otherwise you would have to go through the ramp-up phase again. - -Default locations of the keys folder: - -* Debian/Ubuntu: `/var/lib/tor/keys` -* FreeBSD: `/var/db/tor/keys` - -## Subscribe to the tor-announce mailing list - -This is a very low traffic mailing list and you will get information about new stable tor releases and important security update information. - -* https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-announce - -## Setting up outage notifications - -Once you setup your relay it will likely run without much work from your side. -If something goes wrong it is good to get notified automatically. -We recommend you use one of the free services that allow you to check your relay's ORPorts for reachability and send you an email should they become unreachable for what ever reason. - -UptimeRobot is one of these services that allow you to monitor TCP listeners on arbitrary ports. -This service can check your configured ports once every 5 minutes and send you an email should your tor process die or become unreachable. -This checks only for the listener but does not speak the Tor protocol. - -* https://uptimerobot.com/ - -A good way to monitor a relay for its health state is to have a look at its bandwidth graphs. - -## System Health Monitoring - -To ensure your relay is healthy and not overwhelmed it makes sense to have some basic system monitoring in place to keep an eye on the following metrics: - -* Bandwidth -* Established TCP Connections -* Memory -* Swap -* CPU - -There are many tools for monitoring this kind of data, munin is one of them and is relatively easy to setup. - -Note: **Do not make your private monitoring data graphs public since this could help attackers with deanonymizing Tor users.** - -Some practical advice: - -* If you want to publish traffic statistics, you should aggregate all your relays' traffic over at least a week, then round that to the nearest 10 TiB (terabytes). -* Reporting individual relays is worse than reporting totals for groups of relays. In future, tor will securely aggregate bandwidth statistics, so any individual relay bandwidth reporting will be less secure than tor's statistics. -* Smaller periods are worse. -* Numbers are worse than graphs. -* Real-time data is worse than historical data. -* Data in categories (IP version, in/out, etc.) is worse than total data. - -## Tools - - This section listsm a few tools that you might find handy as a Tor relay operator. - -Nyx: [Nyx](https://nyx.torproject.org/) is a Tor Project tool (formerly arm) that allows you to see real time data of your relay. - -vnstat: vnstat is a command-line tool that shows the amount of data going through your network connection. -You can also use it to generate PNG pictures showing traffic graphs. - -vnstat documentation and demo output: - -* https://humdi.net/vnstat/ -* https://humdi.net/vnstat/cgidemo/ +Click below in which type of relay do you want to host. +--- +_slug: {{setup}}