pitter patter on the keyboard

If you’ve tried to make a backup of your zimbra installation by taring /opt/zimbra you may have noticed the output either fills your available storage or is 80 gigs larger than the actual Zimbra installation.

This is caused by an 80 gig sparse file:

-rw------- zimbra/zimbra 85899345920 2013-03-10 19:40 /opt/zimbra/data/ldap/mdb/db/data.mdb

# ls -lsah /opt/zimbra/data/ldap/mdb/db/
5.6M -rw-------. 1 zimbra zimbra  80G Mar 10 19:40 data.mdb

This appears to be a new feature of Zimbra 8 that was introduced for performance reasons (https://wiki.zimbra.com/wiki/OpenLDAP_Performance_Tuning_8.0#Notes_on_MDB). We can get around it by telling tar to account for sparse-ness:

# tar -Scf zimbra.tar /opt/zimbra/

I started updating a pair of neglected Xen servers a few days ago and I ran into this problem:

xen2 ~ # emerge portage

* IMPORTANT: 3 news items need reading for repository 'gentoo'.
* Use eselect news to read news items.

Calculating dependencies... done!
[ebuild     U ] app-admin/eselect-1.2.11 [1.0.11-r1]
[ebuild  N    ] app-admin/eselect-python-20100321
[uninstall    ] app-admin/eselect-news-20080320
[blocks b     ] app-admin/eselect-news ("app-admin/eselect-news" is blocking app-admin/eselect-1.2.11)
[ebuild  NS   ] dev-lang/python-2.6.6-r2 [2.4.4-r13, 2.5.2-r7] USE="berkdb gdbm ipv6 ncurses readline ssl threads (wide-unicode) xml -build -doc -examples -sqlite -tk -wininst"
[ebuild     U ] sys-apps/portage-2.1.9.42 [2.1.6.7] USE="(ipc%*) -python2% -python3%"
*** Portage will stop merging at this point and reload itself,
then resume the merge.
[blocks B     ] <sys-apps/portage-2.1.9 ("<sys-apps/portage-2.1.9" is blocking dev-lang/python-2.6.6-r2)

This conflict arises on machines which have not been updated since the mainstream python 2 version was upgraded from 2.5 to 2.6. The fix is fairly ham-fisted: untar these files and overlay them on your filesystem:

http://tinderbox.dev.gentoo.org/default-linux/x86/dev-lang/python-2.6.6-r2.tbz2
http://tinderbox.dev.gentoo.org/default-linux/x86/sys-apps/portage-2.1.9.25.tbz2

# tar -xjf portage-2.1.9.25.tar.bz2
# tar -xjf python-2.6.6-r2.tbz2
# cp -ax etc /
# cp -ax usr /

Ignore the warnings about trailing garbage. I’m not sure what’s going on there but it seems to work anyway. Now update the python symlink:

# rm /usr/bin/python
# ln -s /usr/bin/python2.6 /usr/bin/python

Now re-emerge portage and python and you’re on your merry way.