Hello,
I created a shared link, and when the person downloads a file, there are the following errors :
Who have a idea ?
Thank you 
{"reqId":"8RU9p9SMQwj5\/o65hQHf","remoteAddr":"XX.XX.XX.XX","app":"PHP","message":"Error while sending QUERY packet. PID=1576 at \/var\/www\/my_domain.com\/nextcloud\/3rdparty\/doctrine\/dbal\/lib\/Doctrine\/DBAL\/Driver\/PDOStatement.php#91","level":3,"time":"2017-03-02T05:59:36+00:00","method":"GET","url":"\/nextcloud\/s\/MFu3ln7OQP2bmdg\/download?path=%2F&files=FILE.file&downloadStartSecret=XXX","user":"--","version":"11.0.2.7"}
{"reqId":"8RU9p9SMQwj5\/o65hQHf","remoteAddr":"XX.XX.XX.XX","app":"no app in context","message":"Exception: {\"Exception\":\"Doctrine\\\\DBAL\\\\Exception\\\\DriverException\",\"Message\":\"An exception occurred while executing 'SELECT `fileid`, `storage`, `path`, `parent`, `name`, `mimetype`, `mimepart`, `size`, `mtime`,\\n\\t\\t\\t\\t\\t `storage_mtime`, `encrypted`, `etag`, `permissions`, `checksum`\\n\\t\\t\\t\\tFROM `mdc_filecache` WHERE `storage` = ? AND `path_hash` = ?' with params [1, \\\"6f9f954cce6e95dc4fe140bf6f82b750\\\"]:\\n\\nSQLSTATE[HY000]: General error: 2006 MySQL server has gone away\",\"Code\":0,\"Trace\":\"#0 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/3rdparty\\\/doctrine\\\/dbal\\\/lib\\\/Doctrine\\\/DBAL\\\/DBALException.php(128): Doctrine\\\\DBAL\\\\Driver\\\\AbstractMySQLDriver->convertException('An exception oc...', Object(Doctrine\\\\DBAL\\\\Driver\\\\PDOException))\\n#1 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/3rdparty\\\/doctrine\\\/dbal\\\/lib\\\/Doctrine\\\/DBAL\\\/Connection.php(836): Doctrine\\\\DBAL\\\\DBALException::driverExceptionDuringQuery(Object(Doctrine\\\\DBAL\\\\Driver\\\\PDOMySql\\\\Driver), Object(Doctrine\\\\DBAL\\\\Driver\\\\PDOException), 'SELECT `fileid`...', Array)\\n#2 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/DB\\\/Connection.php(194): Doctrine\\\\DBAL\\\\Connection->executeQuery('SELECT `fileid`...', Array, Array, NULL)\\n#3 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Files\\\/Cache\\\/Cache.php(129): OC\\\\DB\\\\Connection->executeQuery('SELECT `fileid`...', Array)\\n#4 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Files\\\/Cache\\\/HomeCache.php(76): OC\\\\Files\\\\Cache\\\\Cache->get('files\\\/Mes vid\\\\xC3\\\\xA9...')\\n#5 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Files\\\/Storage\\\/Wrapper\\\/Encryption.php(141): OC\\\\Files\\\\Cache\\\\HomeCache->get('files\\\/Mes vid\\\\xC3\\\\xA9...')\\n#6 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Files\\\/View.php(1124): OC\\\\Files\\\\Storage\\\\Wrapper\\\\Encryption->filesize('files\\\/Mes vid\\\\xC3\\\\xA9...')\\n#7 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Files\\\/View.php(418): OC\\\\Files\\\\View->basicOperation('filesize', '\\\/Mes vid\\\\xC3\\\\xA9os\\\/Me...')\\n#8 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Files\\\/View.php(437): OC\\\\Files\\\\View->filesize('\\\/Mes vid\\\\xC3\\\\xA9os\\\/Me...')\\n#9 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/legacy\\\/files.php(305): OC\\\\Files\\\\View->readfile('\\\/Mes vid\\\\xC3\\\\xA9os\\\/Me...')\\n#10 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/legacy\\\/files.php(120): OC_Files::getSingleFile(Object(OC\\\\Files\\\\View), '\\\/Mes vid\\\\xC3\\\\xA9os\\\/Me...', 'FILE ...', Array)\\n#11 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/apps\\\/files_sharing\\\/lib\\\/Controller\\\/ShareController.php(529): OC_Files::get('\\\/Mes vid\\\\xC3\\\\xA9os\\\/Me...', 'FILM ...', Array)\\n#12 [internal function]: OCA\\\\Files_Sharing\\\\Controller\\\\ShareController->downloadShare('MFu3ln7OQP2bmdg', 'FILM ...', '\\\/', 'wq19hfiuz9jo')\\n#13 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/AppFramework\\\/Http\\\/Dispatcher.php(160): call_user_func_array(Array, Array)\\n#14 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/AppFramework\\\/Http\\\/Dispatcher.php(90): OC\\\\AppFramework\\\\Http\\\\Dispatcher->executeController(Object(OCA\\\\Files_Sharing\\\\Controller\\\\ShareController), 'downloadShare')\\n#15 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/AppFramework\\\/App.php(114): OC\\\\AppFramework\\\\Http\\\\Dispatcher->dispatch(Object(OCA\\\\Files_Sharing\\\\Controller\\\\ShareController), 'downloadShare')\\n#16 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/public\\\/AppFramework\\\/App.php(136): OC\\\\AppFramework\\\\App::main('ShareController', 'downloadShare', Object(OC\\\\AppFramework\\\\DependencyInjection\\\\DIContainer))\\n#17 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/core\\\/routes.php(99): OCP\\\\AppFramework\\\\App->dispatch('ShareController', 'downloadShare')\\n#18 [internal function]: OC\\\\Route\\\\Router->{closure}(Array)\\n#19 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/private\\\/Route\\\/Router.php(299): call_user_func(Object(Closure), Array)\\n#20 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/lib\\\/base.php(1010): OC\\\\Route\\\\Router->match('\\\/s\\\/MFu3ln7OQP2b...')\\n#21 \\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/index.php(40): OC::handleRequest()\\n#22 {main}\",\"File\":\"\\\/var\\\/www\\\/my_domain.com\\\/nextcloud\\\/3rdparty\\\/doctrine\\\/dbal\\\/lib\\\/Doctrine\\\/DBAL\\\/Driver\\\/AbstractMySQLDriver.php\",\"Line\":116}","level":3,"time":"2017-03-02T05:59:36+00:00","method":"GET","url":"\/nextcloud\/s\/MFu3ln7OQP2bmdg\/download?path=%2F&files=FILE.file&downloadStartSecret=XXX","user":"--","version":"11.0.2.7"}