I have a server with centos 6.3 and cPanel

After the upgrade from php 5.3.16 to php 5.3.19 my site stopped working. When I try to execute an index.php manually, I'm receiving the following error.

php: symbol lookup error: /usr/local/lib/php/extensions/no-debug-non-zts-20090626/memcached.so: undefined symbol: memcached_last_error_errno

Reinstalled memcached and memcache via pecl and manually but that did not help.

What is causing this problem and how do I fix it ?


Memcached 2.x extension in PHP requires a newer version of libmemcached.

So you need to make sure you remove the old one from the system:

yum remove libmemcached

Be sure it removed libmemcached.so.2* from your system.

Download & compile newer libmemcached from https://launchpad.net/libmemcached/+download (for me libmemcached-1.0.13 compiles fine on Centos 6.3)

Recompile memcached extension by issuing:

pecl install -f memcached

Now it should be fine. For me it was.

| improve this answer | |

Check for the "extension=memcached.so" extension entry in new php.ini file. Make sure it is there.

Now run "updatedb && locate memcached.so" to find this module and copy it to /usr/local/lib/php/extensions/no-debug-non-zts-20090626/ location.

| improve this answer | |
  • His issue isn't about PHP not being able to find the extension; there are symbols that are not resolving in the SO file, presumably because he's got an old memcache library than what is required from the PHP extension. – Michael Dec 17 '12 at 12:59

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