Unable to upgrade to 3.0.4

[J. Roeleveld]

Hi all,

I have been trying to upgrade my 2.5.10 installation to 3.0.4.
I follow the steps detailed on the upgrade page:

https://cyrusimap.org/imap/download/upgrade.html

When I get to step "7", I try to connect using a mail-client. This appears to 
work, but I get the following messages in /var/log/messages:

Jan 27 11:32:36 mailtest imap[1249]: login: webtest.vm1.antarean.org 
[10.70.1.102] joost plaintext User logged in 
SESSIONID=<mailtest-1249-1517049156-1-17981315892217922378>
Jan 27 11:32:36 mailtest master[1228]: process type:SERVICE name:imap path:/
usr/libexec/imapd age:0.390s pid:1249 signaled to death by signal 6 (Aborted)
Jan 27 11:32:36 mailtest imap[1252]: login: webtest.vm1.antarean.org 
[10.70.1.102] joost plaintext User logged in 
SESSIONID=<mailtest-1252-1517049156-1-5994302304265644280>
Jan 27 11:32:36 mailtest master[1228]: process type:SERVICE name:imap path:/
usr/libexec/imapd age:0.036s pid:1252 signaled to death by signal 6 (Aborted)


(This continues until I kill the client)

When I connect using "cyradm", I do not see any of the mail folders. (even 
though they were all copied across)

When I try the "reconstruct" command from step 8, I get:

# reconstruct -V max
*** Error in `reconstruct': corrupted double-linked list: 0x000055da30ac7200 
***
======= Backtrace: =========
/lib64/libc.so.6(+0x77a6b)[0x7f13ec42da6b]
/lib64/libc.so.6(+0x7f6de)[0x7f13ec4356de]
/lib64/libc.so.6(+0x829e0)[0x7f13ec4389e0]
/lib64/libc.so.6(realloc+0x176)[0x7f13ec439e36]
/usr/lib64/libcyrus_min.so.0(xrealloc+0xe)[0x7f13ecaa01ce]
/usr/lib64/libcyrus_min.so.0(_buf_ensure+0x8c)[0x7f13eca9bf3c]
/usr/lib64/libcyrus_min.so.0(buf_setmap+0x4b)[0x7f13eca9c37b]
/usr/lib64/libcyrus.so.0(+0x87aa1)[0x7f13ec7ecaa1]
/usr/lib64/libcyrus.so.0(+0x88ce1)[0x7f13ec7edce1]
/usr/lib64/libcyrus_imap.so.0(+0x4deef)[0x7f13ecf2beef]
/usr/lib64/libcyrus_imap.so.0(+0x4e7dc)[0x7f13ecf2c7dc]
/usr/lib64/libcyrus_imap.so.0(mboxlist_findallmulti+0xa6)[0x7f13ecf31d96]
/usr/lib64/libcyrus_imap.so.0(mboxlist_findall+0x7a)[0x7f13ecf31e6a]
reconstruct(+0x264c)[0x55da3088c64c]
/lib64/libc.so.6(__libc_start_main+0xf1)[0x7f13ec3d6541]
reconstruct(+0x278a)[0x55da3088c78a]


The only thing I can think of is that my current mailserver used has 
"unixhierarch = no" and the new one defaults to "yes". But changing the 
setting to "no" in 3.0.4 doesn't resolve this issue either.

Is there anything else I can try? The 3.0.4 installation is purely for test. 
Eg. I have no problems wiping it and starting over. The 2.5.10 is production 
and I am not willing to risk loosing a single email.

Many thanks,

Joost