we need a fix the flakyness of test multichannel.bugs.bug_15346 or mark it as flaky and add a backport for the release branches:

The last 50 lines of log messages:

2026-02-18T09:22:57.402575Z: conn[11]: negprot done
2026-02-18T09:22:57.423613Z: conn[13]: negprot done
2026-02-18T09:22:57.423707Z: conn[8]: echo done
2026-02-18T09:22:57.423744Z: conn[11]: echo done
2026-02-18T09:22:57.443653Z: conn[9]: negprot done
2026-02-18T09:22:57.455611Z: conn[14]: negprot done
2026-02-18T09:22:57.459561Z: conn[13]: echo done
2026-02-18T09:22:57.476706Z: conn[0]: negprot done
2026-02-18T09:22:57.476809Z: conn[9]: echo done
2026-02-18T09:22:57.476851Z: conn[14]: echo done
2026-02-18T09:22:57.492599Z: conn[22]: negprot done
2026-02-18T09:22:57.492702Z: conn[0]: echo done
2026-02-18T09:22:57.500458Z: conn[12]: negprot done
2026-02-18T09:22:57.506582Z: conn[25]: negprot done
2026-02-18T09:22:57.507099Z: conn[22]: echo done
2026-02-18T09:22:57.507318Z: conn[12]: echo done
2026-02-18T09:22:57.512832Z: conn[27]: negprot done
2026-02-18T09:22:57.514539Z: conn[25]: echo done
2026-02-18T09:22:57.518619Z: conn[1]: negprot done
2026-02-18T09:22:57.519537Z: conn[27]: echo done
2026-02-18T09:22:57.527557Z: conn[23]: negprot done
2026-02-18T09:22:57.528052Z: conn[1]: echo done
2026-02-18T09:22:57.534238Z: conn[5]: negprot done
2026-02-18T09:22:57.534891Z: conn[23]: echo done
2026-02-18T09:22:57.540775Z: conn[26]: negprot done
2026-02-18T09:22:57.553494Z: conn[3]: negprot done
2026-02-18T09:22:57.555686Z: conn[5]: echo done
2026-02-18T09:22:57.563383Z: conn[18]: negprot done
2026-02-18T09:22:57.563741Z: conn[3]: echo done
2026-02-18T09:22:57.563892Z: conn[18]: echo done
2026-02-18T09:23:59.603528Z: conn[26]: echo timed out
UNEXPECTED(failure): samba3.smb2.multichannel.bugs.bug_15346(ad_dc)
REASON: Exception: Exception: ../../source4/torture/smb2/multichannel.c:2474: status was NT_STATUS_IO_TIMEOUT, expected NT_STATUS_OK: smb2cli_echo_recv failed

FAILED (1 failures, 0 errors and 0 unexpected successes in 0 testsuites)

There might be more detail in /m/bjacke/a424/b645748/samba-ad-dc-1/./bin/ab/subunit or /m/bjacke/a424/b645748/samba-ad-dc-1/./bin/ab/summary.
TOP 10 slowest tests
samba3.smb2.session krb5(ad_dc) -> 167
samba3.smb2.replay(ad_dc) -> 60