Bug #39353

Updated by Nathan Cutler 10 months ago

Under certain circumstances, an attempt to increase the PG count of a pool can fail like this:

$ ceph osd pool set foopool pg_num 512
Error E2BIG: specified pg_num 512 is too large (creating 504 new PGs on ~8 OSDs exceeds per-OSD max of 32)

This error can be addressed in two ways: either by increasing mon_osd_max_split_count or by simply increasing the pg_num in smaller increments. However, the error message does not mention either possibility.

This issue affects only mimic and luminous, because the error message (and indeed the mon_osd_max_split_count option itself) was removed in Nautilus.

The issue was partially addressed by in Mimic.