[Bitrix\Main\DB\SqlQueryException] 
Mysql query error: (2006) MySQL server has gone away (400)
SET NAMES 'cp1251'
/home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:138
#0: Bitrix\Main\DB\MysqliConnection->queryInternal(string, array, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:329
#1: Bitrix\Main\DB\Connection->query(string, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:378
#2: Bitrix\Main\DB\Connection->queryExecute(string)
	/home/bitrix/www/bitrix/php_interface/after_connect_d7.php:3
#3: include(string)
	/home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:82
#4: Bitrix\Main\DB\MysqliConnection->connectInternal()
	/home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:123
#5: Bitrix\Main\DB\MysqliConnection->queryInternal(string, NULL, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:329
#6: Bitrix\Main\DB\Connection->query(string, NULL, integer, integer)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:357
#7: Bitrix\Main\DB\Connection->queryScalar(string)
	/home/bitrix/www/bitrix/modules/security/lib/session.php:111
#8: Bitrix\Security\SessionTable::lock(string, integer)
	/home/bitrix/www/bitrix/modules/security/classes/general/session_db.php:52
#9: CSecuritySessionDB::read(string)
	
#10: session_start()
	/home/bitrix/www/bitrix/modules/main/include.php:285
#11: require_once(string)
	/home/bitrix/www/bitrix/modules/main/include/prolog_before.php:16
#12: require_once(string)
	/home/bitrix/www/bitrix/modules/main/include/prolog.php:11
#13: require_once(string)
	/home/bitrix/www/bitrix/header.php:1
#14: require(string)
	/home/bitrix/www/news/index.php:2
#15: include_once(string)
	/home/bitrix/www/bitrix/modules/main/include/urlrewrite.php:159
#16: include_once(string)
	/home/bitrix/www/bitrix/urlrewrite.php:2

Fatal error: Uncaught exception 'Bitrix\Main\DB\SqlQueryException' with message 'Mysql query error: (2006) MySQL server has gone away' in /home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:138 Stack trace: #0 /home/bitrix/www/bitrix/modules/main/lib/db/mysqlcommonconnection.php(132): Bitrix\Main\DB\MysqliConnection->queryInternal('SELECT * FROM `...') #1 /home/bitrix/www/bitrix/modules/main/lib/db/connection.php(715): Bitrix\Main\DB\MysqlCommonConnection->getTableFields('b_sec_session') #2 /home/bitrix/www/bitrix/modules/main/lib/db/sqlhelper.php(362): Bitrix\Main\DB\Connection->getTableField('b_sec_session', 'SESSION_ID') #3 /home/bitrix/www/bitrix/modules/main/lib/entity/datamanager.php(799): Bitrix\Main\DB\SqlHelper->prepareAssignment('b_sec_session', 'SESSION_ID', 'uj6fCgWx5Y7T7pS...') #4 /home/bitrix/www/bitrix/modules/security/classes/general/session_db.php(87): Bitrix\Main\Entity\DataManager::delete('uj6fCgWx5Y7T7pS...') #5 [internal function]: CSecuritySessionDB::write('uj6fCgWx5Y7T7pS...', '') #6 [i in /home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php on line 138