We modified the fallback behaviour when we merged the exponential backoff code in 0.2.9.1-alpha, and again in legacy/trac#17750: ``` /* With the ClientBootstrapConsensus*Download* below: * Clients with only authorities will try: * - 3 authorities over 10 seconds, then wait 60 minutes. * Clients with authorities and fallbacks will try: * - 2 authorities and 4 fallbacks over 21 seconds, then wait 60 minutes. * Clients will also retry when an application request arrives. * After a number of failed reqests, clients retry every 3 days + 1 hour. * * Clients used to try 2 authorities over 10 seconds, then wait for * 60 minutes or an application request. * * When clients have authorities and fallbacks available, they use these * schedules: (we stagger the times to avoid thundering herds) */ V(ClientBootstrapConsensusAuthorityDownloadSchedule, CSV_INTERVAL, "6, 11, 3600, 10800, 25200, 54000, 111600, 262800" /* 3 days + 1 hour */), V(ClientBootstrapConsensusFallbackDownloadSchedule, CSV_INTERVAL, "0, 1, 4, 11, 3600, 10800, 25200, 54000, 111600, 262800"), /* When clients only have authorities available, they use this schedule: */ V(ClientBootstrapConsensusAuthorityOnlyDownloadSchedule, CSV_INTERVAL, "0, 3, 7, 3600, 10800, 25200, 54000, 111600, 262800"), ``` The behaviour is now: ``` /* With the ClientBootstrapConsensus*Download* below: * Clients with only authorities will try: * - at least 3 authorities over 10 seconds, then exponentially backoff, * with the next attempt 3-21 seconds later, * Clients with authorities and fallbacks will try: * - at least 2 authorities and 4 fallbacks over 21 seconds, then * exponentially backoff, with the next attempts 4-33 seconds later, * Clients will also retry when an application request arrives. * After a number of failed requests, clients retry every 3 days + 1 hour. * * Clients used to try 2 authorities over 10 seconds, then wait for * 60 minutes or an application request. ```