Second Snowflake bridge available for testing

The Snowflake team has done a lot of work on “vertical” scaling of the snowflake-01 bridge, making the host capable of handling more concurrent users. They are also now doing “horizontal” scaling, by setting up a new snowflake-02 bridge to share the load. The second bridge is scheduled to be enabled in the next Tor Browser alpha release, 12.0a5, but you can test it yourself now, by entering a bridge line manually.

Short instructions: take any working Snowflake bridge line, and change the fingerprint 2B280B23E1107BB62ABFC40DDCC8824814F80A72 to 8838024498816A039FCBBAB14E6F40A0843051FA. There are two places where you need to change the fingerprint.

Longer instructions:

  • In Tor Browser for desktop, go to (hamburger menu) → SettingsConnectionBridges, then click the Add a Bridge Manually… button.
  • In Tor Browser for Android, go to :gear: (settings) → Config Bridge. Toggle Use a Bridge to “on” and tap Provide a Bridge I know.
  • Paste in the bridge line
    snowflake 192.0.2.4:80 8838024498816A039FCBBAB14E6F40A0843051FA fingerprint=8838024498816A039FCBBAB14E6F40A0843051FA url=https://snowflake-broker.torproject.net.global.prod.fastly.net/ front=cdn.sstatic.net ice=stun:stun.l.google.com:19302,stun:stun.altar.com.pl:3478,stun:stun.antisip.com:3478,stun:stun.bluesip.net:3478,stun:stun.dus.net:3478,stun:stun.epygi.com:3478,stun:stun.sonetel.com:3478,stun:stun.sonetel.net:3478,stun:stun.stunprotocol.org:3478,stun:stun.uls.co.za:3478,stun:stun.voipgate.com:3478,stun:stun.voys.nl:3478 utls-imitate=hellorandomizedalpn

To check if it’s working, you can check the Tor log for a new bridge descriptor line. flakeyN is the snowflake-01 bridge; crustyN is the snowflake-02 bridge.

[NOTICE] new bridge descriptor 'crusty3' (fresh): $8838024498816A039FCBBAB14E6F40A0843051FA~crusty3 [tO9nYvNCAdAh9lPoEEv2pZ9BJq+YzmPAMY6pxoFrLuk] at 192.0.2.4

The purpose of the second bridge is to increase capacity. It will not have any effect on blocking resistance. It does not change anything about broker interaction or the way the Snowflake client interacts with proxies.

We will likely need to restart the snowflake-02 bridge multiple times over the coming days for upgrades and configuration changes, so be aware there may be some disruption in availability.