{}Context{}

This bug was discovered during testing on the dedicated elegant step-down feature branch https://github.com/wiredtiger/wiredtiger/compare/develop...wt-17785-enable-elegant-stepdown-mainine. Currently, step-down restarts for test/format. In this branch, we are replacing the restart with a synchronous, elegant step-down triggered via reconfigure(role=follower). This ticket captures one of the bugs as a result of elegant stepdown.

{}Evergreen Task / Link:{} https://spruce.corp.mongodb.com/task/wiredtiger_ubuntu2004_stress_tests_arm64_format_stress_test_disagg_switch_data_validation_1_patch_9dd7114d26cbe9226ad97fb12c94a99ea1f8b52f_6a28f82d40102300072af7f8_26_06_10_05_38_08/logs?execution=0

{}Logs & Stack Trace{}

mirror: 5352/5357 mismatch: table:T00001:

{0000005352.00/opqrstuv}

/

{0000005352/LMNOPQRSTUV}

, table:T00002:

{0000005357.00/opqrstuvwxyzabcdefgh}

/

{0000005357/LMNO-------wvutsrkjihgr---vdcba}

t: FAILED: table_verify_mirror/354: base_keyno == table_keyno || (FLD_ISSET(g.trace_flags, TRACE_MIRROR_FAIL) && failures < 20)
#4 table_verify_mirror (test/format/verify.c:354) -> #5 wts_verify_mirrors (verify.c:460) -> __wt_abort