libmemcache Cannot load mod_auth_memcookie.so into server: libmemcache.so.0: undefined symbol: mcm_buf_len

[Paul Egges]

This is for Ubuntu 14.04 LTS
Release: 14.04

Package: libmemcache0 1.4.0.rc2-1ubuntu1

Cannot start apache: An error message similar to the following occurs :

Cannot load mod_auth_memcookie.so into server: /usr/lib/libmemcache.so : undefined symbol: mcm_buf_len

We use mod_auth_memcookie with Apache2. The following mods were installed:

ls mods-enabled:

access_compat.load authz_groupfile.load cgi.load env.load mpm_prefork.load proxy_ajp.load reqtimeout.load setenvif.conf ssl.load wsgi.load
alias.conf auth_memcookie.load authz_host.load deflate.conf filter.load negotiation.conf proxy.conf server2.crt setenvif.load status.conf
alias.load authn_core.load authz_user.load deflate.load mime.conf negotiation.load proxy_http.load server2.csr shib2.load
auth_basic.load authn_file.load autoindex.conf dir.conf mime.load php5.conf proxy.load server2.key socache_shmcb.load status.load
auth_memcookie.conf authz_core.load autoindex.load dir.load mpm_prefork.conf php5.load reqtimeout.conf server2.key.secure ssl.conf wsgi.conf

Server version: Apache/2.4.7 (Ubuntu)
Server built: Apr 3 2014 12:20:28

This fixed the problem:

go to the libmemcache directory, example: cd $HOME/libmemcache-1.4.0.rc2
wget 'http://svnweb.freebsd.org/ports/head/databases/libmemcache/files/patch-fix-inline?revision=248965&view=co' -O libcache.patch
patch -p0 < libcache.patch

And then building and reinstalling libmemcache

See additional information here (it refers to Fedora, but the patch seems to work for Ubuntu also):
http://pietercvdmlinux.blogspot.com/2012/07/building-modauthmemcookie-on-fedora.html

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Clayton Kramer (clayton-kramer)]

Thanks for providing the patched file Paul.

[Harald Hannelius (harald-arcada)]

Still bitten by this on LTS 16.04.3. This seems to be the same bug https://bugs.launchpad.net/ubuntu/+source/libapache2-mod-auth-memcookie/+bug/1461351