Hi! I'm not familiar with exact reasons for rollback break in this case and if it's possible to e.g. backport to the last LTS.
However, we discussed formal procedure and process for storage changes here: https://github.com/prometheus/proposals/pull/40 - give us feedback on this! This is for WAL but I might extend this to TSDB blocks. TL;DR is to support rollback to at least one LTS version back. Kind Regards, Bartek Plotka @bwplotka On Friday, January 24, 2025 at 12:58:40 AM UTC Gavine wrote: > Hi Prometheus Dev Group, > > As we know, Prometheus v3 will introduce a breaking change to TSDB, > specifically the index format V3, with v2.55.0 serving as the migration > gateway. > > Our product has a requirement to support rollback from v3 to versions > prior to v2.55.0. Could we have your opinion on this? Specifically, do you > foresee any issues if we develop a conversion tool to change the version > number in the index files back to 2 before a rollback? > > From what we understand, Prometheus v2 (starting from certain older > versions) has already stopped reading/parsing the fields removed in format > V3, i.e. Label Index 1...N and the Label Index Table, correct? By reviewing > the related changes in v2.55.0, it seems the modifications were primarily > to make format V3 recognizable while applying the same logic as format V2. > > Is there anything else we should consider for such a rollback mechanism? > > Thanks in advance for your insights! > > Best regards, > > Gavine > -- You received this message because you are subscribed to the Google Groups "Prometheus Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/prometheus-developers/b875f03e-6f00-47c6-a50c-4bbd809d0631n%40googlegroups.com.
