S2_Nodes_Pcache_Exception: Can't start nodes cache system // trace

exception 'S2_Nodes_Mcache_Exception' with message 'Can't connect to memcached server' in /var/www/london.simbix.com/private_php/_core/Main.php:8
Stack trace:
#0 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Mcache->__construct()
#1 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Mcache::getInstance()
#2 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Pcache->__construct(Array, Array)
#3 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Pcache::getInstance(Array, Array)
#4 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Module_Common->_pcache_initialize()
#5 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Module_Common_Prototype->__construct(Array, 'projects')
#6 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Prototype->getHandler('projects')
#7 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes->e('main')
#8 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes->__construct('main')
#9 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main->getProject('main')
#10 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main->getProject('marsh')
#11 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method->setContext('marsh', NULL)
#12 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method->__construct()
#13 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method::getInstance()
#14 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main_Api->Register()
#15 /var/www/london.simbix.com/private_php/_core/main.d.php(8): S2_Main_Helper::registerAPI()
#16 /var/www/london.simbix.com/private_php/_core/main.d.php(8): S2->Startup()
#17 {PATH_PUB}/_index.php(11): require('/var/www/london...')
#18 {main}

Next exception 'S2_Nodes_Mcache_Exception' with message 'Can't start "S2_Nodes_Mcache" class' in /var/www/london.simbix.com/private_php/_core/Main.php:8
Stack trace:
#0 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Mcache->__construct()
#1 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Mcache::getInstance()
#2 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Pcache->__construct(Array, Array)
#3 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Pcache::getInstance(Array, Array)
#4 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Module_Common->_pcache_initialize()
#5 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Module_Common_Prototype->__construct(Array, 'projects')
#6 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Prototype->getHandler('projects')
#7 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes->e('main')
#8 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes->__construct('main')
#9 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main->getProject('main')
#10 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main->getProject('marsh')
#11 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method->setContext('marsh', NULL)
#12 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method->__construct()
#13 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method::getInstance()
#14 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main_Api->Register()
#15 /var/www/london.simbix.com/private_php/_core/main.d.php(8): S2_Main_Helper::registerAPI()
#16 /var/www/london.simbix.com/private_php/_core/main.d.php(8): S2->Startup()
#17 {PATH_PUB}/_index.php(11): require('/var/www/london...')
#18 {main}

Next exception 'S2_Nodes_Pcache_Exception' with message 'Can't start nodes cache system' in /var/www/london.simbix.com/private_php/_core/Main.php:8
Stack trace:
#0 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Pcache->__construct(Array, Array)
#1 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Pcache::getInstance(Array, Array)
#2 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Module_Common->_pcache_initialize()
#3 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Module_Common_Prototype->__construct(Array, 'projects')
#4 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes_Prototype->getHandler('projects')
#5 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes->e('main')
#6 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Nodes->__construct('main')
#7 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main->getProject('main')
#8 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main->getProject('marsh')
#9 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method->setContext('marsh', NULL)
#10 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method->__construct()
#11 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Method::getInstance()
#12 /var/www/london.simbix.com/private_php/_core/Main.php(8): S2_Main_Api->Register()
#13 /var/www/london.simbix.com/private_php/_core/main.d.php(8): S2_Main_Helper::registerAPI()
#14 /var/www/london.simbix.com/private_php/_core/main.d.php(8): S2->Startup()
#15 {PATH_PUB}/_index.php(11): require('/var/www/london...')
#16 {main}

Simbix Framework/2.1.6, Apache/2.2.16 (Debian) Aborting...