[Bitrix\Main\DB\SqlQueryException] 
Mysql query error: (2006) MySQL server has gone away (400)
SELECT 
	`iblock_iblock_site`.`IBLOCK_ID` AS `IBLOCK_ID`
FROM `b_iblock_site` `iblock_iblock_site` 
LEFT JOIN `b_iblock` `iblock_iblock_site_iblock` ON `iblock_iblock_site`.`IBLOCK_ID` = `iblock_iblock_site_iblock`.`ID`
WHERE (`iblock_iblock_site`.`IBLOCK_ID` in (2))
AND `iblock_iblock_site`.`SITE_ID` = 's1'
AND `iblock_iblock_site_iblock`.`ACTIVE` = 'Y'
/home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:137
#0: Bitrix\Main\DB\MysqliConnection->queryInternal(string, array, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:330
#1: Bitrix\Main\DB\Connection->query(string)
	/home/bitrix/www/bitrix/modules/main/lib/entity/query.php:3038
#2: Bitrix\Main\Entity\Query->query(string)
	/home/bitrix/www/bitrix/modules/main/lib/entity/query.php:797
#3: Bitrix\Main\Entity\Query->exec()
	/home/bitrix/www/bitrix/modules/main/lib/entity/datamanager.php:290
#4: Bitrix\Main\Entity\DataManager::getList(array)
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:3585
#5: Bitrix\Iblock\Component\Base->checkIblock()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:3551
#6: Bitrix\Iblock\Component\Base->processResultData()
	/home/bitrix/www/bitrix/components/bitrix/catalog.section/class.php:90
#7: CatalogSectionComponent->processResultData()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:3971
#8: Bitrix\Iblock\Component\Base->loadData()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/elementlist.php:1058
#9: Bitrix\Iblock\Component\ElementList->loadData()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:3960
#10: Bitrix\Iblock\Component\Base->initialLoadAction()
	/home/bitrix/www/bitrix/components/bitrix/catalog.section/class.php:327
#11: CatalogSectionComponent->initialLoadAction()
	
#12: call_user_func(array)
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:4145
#13: Bitrix\Iblock\Component\Base->doAction()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:4163
#14: Bitrix\Iblock\Component\Base->executeComponent()
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:638
#15: CBitrixComponent->includeComponent(string, array, object)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:1041
#16: CAllMain->IncludeComponent(string, string, array, object)
	/home/bitrix/www/bitrix/templates/.default/components/bitrix/catalog/catalog_2017/element.php:314
#17: include(string)
	/home/bitrix/www/bitrix/modules/main/classes/general/component_template.php:720
#18: CBitrixComponentTemplate->__IncludePHPTemplate(array, array, string)
	/home/bitrix/www/bitrix/modules/main/classes/general/component_template.php:815
#19: CBitrixComponentTemplate->IncludeTemplate(array)
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:735
#20: CBitrixComponent->showComponentTemplate()
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:683
#21: CBitrixComponent->includeComponentTemplate(string)
	/home/bitrix/www/bitrix/components/bitrix/catalog/component.php:171
#22: include(string)
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:594
#23: CBitrixComponent->__includeComponent()
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:653
#24: CBitrixComponent->includeComponent(string, array, boolean)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:1041
#25: CAllMain->IncludeComponent(string, string, array, boolean)
	/home/bitrix/www/catalog/index.php:2492
#26: include_once(string)
	/home/bitrix/www/bitrix/modules/main/include/urlrewrite.php:159
#27: include_once(string)
	/home/bitrix/www/bitrix/urlrewrite.php:5

Fatal error: Uncaught Bitrix\Main\DB\SqlQueryException: Mysql query error: (2006) MySQL server has gone away in /home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:137 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(716): Bitrix\Main\DB\MysqlCommonConnection->getTableFields('b_sec_session') #2 /home/bitrix/www/bitrix/modules/main/lib/db/sqlhelper.php(387): Bitrix\Main\DB\Connection->getTableField('b_sec_session', 'SESSION_ID') #3 /home/bitrix/www/bitrix/modules/main/lib/entity/datamanager.php(974): Bitrix\Main\DB\SqlHelper->prepareAssignment('b_sec_session', 'SESSION_ID', '5WvDSp9rmdtj9EE...') #4 /home/bitrix/www/bitrix/modules/security/classes/general/session_db.php(92): Bitrix\Main\Entity\DataManager::delete(Array) #5 [internal function]: CSecuritySessionDB::write('5WvDSp9rmdtj9EE...', 'SESS_AUTH|a:1:{...') #6 [internal function]: sess in /home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php on line 137