Exception: Failed to start session

[kaipee]

Steps to reproduce

Unknown what caused the issue. Errors are shown in Administration > Logging

Expected behaviour

No errors

Actual behaviour

Errors

Server configuration detail

Operating system: Linux 4.15.0-74-generic #84-Ubuntu SMP Thu Dec 19 08:06:28 UTC 2019 x86_64

Webserver: Apache (fpm-fcgi)

Database: pgsql PostgreSQL 10.10 (Ubuntu 10.10-0ubuntu0.18.04.1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0, 64-bit

PHP version:

7.2.24-0ubuntu0.18.04.2
Modules loaded: Core, date, libxml, openssl, pcre, zlib, filter, hash, Reflection, SPL, sodium, session, standard, cgi-fcgi, json, apcu, igbinary, PDO, xml, bz2, calendar, ctype, curl, dom, mbstring, fileinfo, ftp, gd, gettext, gmp, iconv, imagick, imap, intl, redis, ldap, exif, pdo_pgsql, pgsql, Phar, posix, readline, shmop, SimpleXML, smbclient, soap, sockets, sysvmsg, sysvsem, sysvshm, tokenizer, wddx, xmlreader, xmlwriter, xsl, zip, libsmbclient, Zend OPcache

Nextcloud version: 17.0.2 - 17.0.2.1

Updated from an older Nextcloud/ownCloud or fresh install:

Where did you install Nextcloud from: unknown

Signing status

Array
(
)

List of activated apps

Enabled:
 - accessibility: 1.3.0
 - activity: 2.10.1
 - admin_audit: 1.7.0
 - audioplayer: 2.9.0
 - bookmarks: 2.3.4
 - calendar: 2.0.1
 - cloud_federation_api: 1.0.0
 - comments: 1.7.0
 - contacts: 3.1.8
 - dav: 1.13.0
 - drawio: 0.9.4
 - extract: 1.2.3
 - federatedfilesharing: 1.7.0
 - federation: 1.7.0
 - files: 1.12.0
 - files_accesscontrol: 1.7.0
 - files_external: 1.8.0
 - files_markdown: 2.2.0
 - files_mindmap: 0.0.15
 - files_pdfviewer: 1.6.0
 - files_rightclick: 0.15.1
 - files_sharing: 1.9.0
 - files_trashbin: 1.7.0
 - files_versions: 1.10.0
 - files_videoplayer: 1.6.0
 - firstrunwizard: 2.6.0
 - gallery: 18.4.0
 - impersonate: 1.4.0
 - issuetemplate: 0.6.0
 - logreader: 2.2.0
 - lookup_server_connector: 1.5.0
 - nextbackup: 19.12.1
 - nextcloud_announcements: 1.6.0
 - notes: 3.1.1
 - notifications: 2.5.0
 - oauth2: 1.5.0
 - password_policy: 1.7.0
 - previewgenerator: 2.2.0
 - privacy: 1.1.0
 - provisioning_api: 1.7.0
 - qownnotesapi: 20.1.0
 - recommendations: 0.5.0
 - serverinfo: 1.7.0
 - sharebymail: 1.7.0
 - support: 1.0.1
 - survey_client: 1.5.0
 - suspicious_login: 3.0.1
 - systemtags: 1.7.0
 - tasks: 0.11.3
 - text: 1.1.1
 - theming: 1.8.0
 - twofactor_backupcodes: 1.6.0
 - updatenotification: 1.7.0
 - viewer: 1.2.0
 - workflowengine: 1.7.0
Disabled:
 - encryption
 - user_ldap

Configuration (config/config.php)

{
    "passwordsalt": "***REMOVED SENSITIVE VALUE***",
    "secret": "***REMOVED SENSITIVE VALUE***",
    "trusted_domains": [
        "localhost",
        "192.168.0.78",
        "nextcloud",
        "nextcloud.kphm.kaipee.co.uk",
        "kphmsrv.kaipee.co.uk"
    ],
    "datadirectory": "***REMOVED SENSITIVE VALUE***",
    "dbtype": "pgsql",
    "version": "17.0.2.1",
    "overwrite.cli.url": "https:\/\/nextcloud.kphm.kaipee.co.uk\/",
    "dbname": "***REMOVED SENSITIVE VALUE***",
    "dbhost": "***REMOVED SENSITIVE VALUE***",
    "dbport": "",
    "dbtableprefix": "oc_",
    "dbuser": "***REMOVED SENSITIVE VALUE***",
    "dbpassword": "***REMOVED SENSITIVE VALUE***",
    "installed": true,
    "instanceid": "***REMOVED SENSITIVE VALUE***",
    "log_type": "file",
    "logfile": "\/var\/log\/nextcloud\/nextcloud.log",
    "loglevel": "2",
    "mail_smtpmode": "smtp",
    "remember_login_cookie_lifetime": "1800",
    "log_rotate_size": "10485760",
    "trashbin_retention_obligation": "auto, 180",
    "versions_retention_obligation": "auto, 365",
    "simpleSignUpLink.shown": "false",
    "memcache.local": "\\OC\\Memcache\\APCu",
    "filelocking.enabled": true,
    "memcache.distributed": "\\OC\\Memcache\\Redis",
    "memcache.locking": "\\OC\\Memcache\\Redis",
    "redis": {
        "host": "***REMOVED SENSITIVE VALUE***",
        "port": 0,
        "timeout": 0.5,
        "dbindex": 0,
        "password": "***REMOVED SENSITIVE VALUE***"
    },
    "logtimezone": "Europe\/London",
    "htaccess.RewriteBase": "\/",
    "enable_previews": true,
    "enabledPreviewProviders": [
        "OC\\Preview\\PNG",
        "OC\\Preview\\JPEG",
        "OC\\Preview\\GIF",
        "OC\\Preview\\BMP",
        "OC\\Preview\\MarkDown",
        "OC\\Preview\\MP3",
        "OC\\Preview\\TXT",
        "OC\\Preview\\Movie",
        "OC\\Preview\\Photoshop",
        "OC\\Preview\\SVG",
        "OC\\Preview\\TIFF"
    ],
    "preview_max_x": "2048",
    "preview_max_y": "2048",
    "jpeg_quality": "60",
    "maintenance": false,
    "mail_smtpsecure": "tls",
    "mail_sendmailmode": "smtp",
    "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
    "mail_smtpport": "587",
    "mail_from_address": "***REMOVED SENSITIVE VALUE***",
    "mail_domain": "***REMOVED SENSITIVE VALUE***",
    "mail_smtpauthtype": "LOGIN",
    "mail_smtpauth": 1,
    "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
    "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
    "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
    "overwritehost": "kphmsrv.kaipee.co.uk:58443",
    "overwriteprotocol": "https",
    "overwritecondaddr": "^192\\.168\\.0\\.77$"
}

Are you using external storage, if yes which one: local/smb/sftp/...

Are you using encryption:

Are you using an external user-backend, if yes which one: LDAP/ActiveDirectory/Webdav/...

Client configuration

Browser: Mozilla/5.0 (X11; Linux x86_64; rv:72.0) Gecko/20100101 Firefox/72.0

Operating system:

Logs

Web server error log

Insert your web server log here 

Nextcloud log

[base] Error: Exception: Failed to start session at <<closure>>

0. /var/www/nextcloud/lib/base.php line 424
   OC\Session\Internal->__construct("ocuezijab7zo")
1. /var/www/nextcloud/lib/base.php line 642
   OC::initSession()
2. /var/www/nextcloud/lib/base.php line 1078
   OC::init()
3. /var/www/nextcloud/index.php line 40
   undefinedundefinedrequire_once("/var/www/nextcloud/lib/base.php")

GET /login
from **.**.**.** at 2020-01-25T18:18:48+00:00

Browser log

Insert your browser log here, this could for example include:

a) The javascript console log
b) The network log
c) ...

[kesselb]

server/lib/private/Session/Internal.php

Lines 64 to 66 in ca964cf

	if (!isset($_SESSION)) {
	throw new \Exception('Failed to start session');
	}

That's the code in question. I have no idea how to run into such a situation. You changed some sessions related settings with php / the session.save_path is writeable?

[kaipee]

Nope I haven't modified any PHP files on the server.

Where would the session.save_path be located?

[kesselb]

Where would the session.save_path be located?

https://www.php.net/manual/en/session.configuration.php#ini.session.save-path

[kaipee]

root@nextcloud:/var/www# php -i | grep php.ini
Configuration File (php.ini) Path => /etc/php/7.2/cli
Loaded Configuration File => /etc/php/7.2/cli/php.ini

root@nextcloud:/var/www# php -i | grep save_path
session.save_path => /var/lib/php/sessions => /var/lib/php/sessions

root@nextcloud:/var/www# ls -ald /var/lib/php/sessions
drwx-wx-wt 2 root root 12288 Jan 29 18:41 /var/lib/php/sessions

root@nextcloud:/var/www# ls -al /var/lib/php/sessions/
total 92
drwx-wx-wt 2 root     root     12288 Jan 29 18:41 .
drwxr-xr-x 4 root     root      4096 Jan  2 19:05 ..
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_19hjhbr15al1qhruusndaa9pls
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_3l5eti8tmhr1q31k3vh31phb69
-rw------- 1 www-data www-data   403 Jan 29 18:59 sess_6ahngl31hl2le8ahj2kti5kde5
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_7m9fqfnhjkd27pmluckd4cmuvl
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_7pulms379n1frqenfma60j5lj4
-rw------- 1 www-data www-data   787 Jan 29 18:38 sess_94u3igr4p775c4bbofnfjhnmo4
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_9q3qa9p1pnunbs5fj1nvpg7nke
-rw------- 1 www-data www-data   787 Jan 29 18:38 sess_bd63kt6res0bofihg0qu37rqnp
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_bmt8kdpi2obkt7bp5ltpm8o29c
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_c9f3vegri9f1qnhsug1niqddt8
-rw------- 1 www-data www-data   787 Jan 29 18:38 sess_cps231mbp3t4t7edtg51nr35uh
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_fc8g2ntlltscmr402gkbhdgsg0
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_getlp20ihulpvi81vsru1qac88
-rw------- 1 www-data www-data   787 Jan 29 18:38 sess_hqg43j6ps440jl6u5or7f9iqff
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_ja6v2jb2p6lpd9poenfs1mcrgd
-rw------- 1 www-data www-data   403 Jan 29 18:22 sess_ltkarn7uuo1p85k30ak6p3ihf0
-rw------- 1 www-data www-data   787 Jan 29 18:41 sess_nf1u3h6qcshenalsknj1u5irfn
-rw------- 1 www-data www-data   787 Jan 29 18:38 sess_qemptirm43cu6iuf0fi5uahvec
-rw------- 1 www-data www-data   403 Jan 29 18:59 sess_t8en67up4u7n2bigqpfbf1jdpu

[kaipee]

root@nextcloud:/var/www# find / -type f -iname "php.ini"
/etc/php/7.2/cli/php.ini
/etc/php/7.2/fpm/php.ini
/var/www/nextcloud/apps/nextbackup/tests/travis/php.ini
/var/www/nextcloud/apps/qownnotesapi/tests/travis/php.ini

Here are both php.ini files (filtered for 'session')

/etc/php/7.2/cli/php.ini

session
session.auto_start => Off => Off
session.cache_expire => 180 => 180
session.cache_limiter => nocache => nocache
session.cookie_domain => no value => no value
session.cookie_httponly => no value => no value
session.cookie_lifetime => 0 => 0
session.cookie_path => / => /
session.cookie_secure => 0 => 0
session.gc_divisor => 1000 => 1000
session.gc_maxlifetime => 1440 => 1440
session.gc_probability => 0 => 0
session.lazy_write => On => On
session.name => PHPSESSID => PHPSESSID
session.referer_check => no value => no value
session.save_handler => files => files
session.save_path => /var/lib/php/sessions => /var/lib/php/sessions
session.serialize_handler => php => php
session.sid_bits_per_character => 5 => 5
session.sid_length => 26 => 26
session.upload_progress.cleanup => On => On
session.upload_progress.enabled => On => On
session.upload_progress.freq => 1% => 1%
session.upload_progress.min_freq => 1 => 1
session.upload_progress.name => PHP_SESSION_UPLOAD_PROGRESS => PHP_SESSION_UPLOAD_PROGRESS
session.upload_progress.prefix => upload_progress_ => upload_progress_
session.use_cookies => 1 => 1
session.use_only_cookies => 1 => 1
session.use_strict_mode => 0 => 0
session.use_trans_sid => 0 => 0
session.trans_sid_hosts => no value => no value
session.trans_sid_tags => a=href,area=href,frame=src,form= => a=href,area=href,frame=src,form=

/etc/php/7.2/fpm/php.ini

session
session.auto_start => Off => Off
session.cache_expire => 180 => 180
session.cache_limiter => nocache => nocache
session.cookie_domain => no value => no value
session.cookie_httponly => no value => no value
session.cookie_lifetime => 0 => 0
session.cookie_path => / => /
session.cookie_secure => 0 => 0
session.gc_divisor => 1000 => 1000
session.gc_maxlifetime => 1440 => 1440
session.gc_probability => 0 => 0
session.lazy_write => On => On
session.name => PHPSESSID => PHPSESSID
session.referer_check => no value => no value
session.save_handler => files => files
session.save_path => /var/lib/php/sessions => /var/lib/php/sessions
session.serialize_handler => php => php
session.sid_bits_per_character => 5 => 5
session.sid_length => 26 => 26
session.upload_progress.cleanup => On => On
session.upload_progress.enabled => On => On
session.upload_progress.freq => 1% => 1%
session.upload_progress.min_freq => 1 => 1
session.upload_progress.name => PHP_SESSION_UPLOAD_PROGRESS => PHP_SESSION_UPLOAD_PROGRESS
session.upload_progress.prefix => upload_progress_ => upload_progress_
session.use_cookies => 1 => 1
session.use_only_cookies => 1 => 1
session.use_strict_mode => 0 => 0
session.use_trans_sid => 0 => 0
session.trans_sid_hosts => no value => no value
session.trans_sid_tags => a=href,area=href,frame=src,form= => a=href,area=href,frame=src,form=

This issue has been automatically marked as stale because it has not had recent activity and seems to be missing some essential information. It will be closed if no further activity occurs. Thank you for your contributions.

[kaipee]

Issue still persists

[kesselb]

Hmm. $_SESSION is not available. That's a php internal. I doubt that has anything to do with Nextcloud.

Index: lib/private/Session/Internal.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- lib/private/Session/Internal.php	(revision 90c3e3bbeb566f73952f7e4c66b9f98ec84cdde2)
+++ lib/private/Session/Internal.php	(date 1582987817704)
@@ -54,15 +54,17 @@
 	 */
 	public function __construct(string $name) {
 		set_error_handler([$this, 'trapError']);
+		$error = '';
 		$this->invoke('session_name', [$name]);
 		try {
 			$this->startSession();
 		} catch (\Exception $e) {
+			$error = $e->getMessage();
 			setcookie($this->invoke('session_name'), '', -1, \OC::$WEBROOT ?: '/');
 		}
 		restore_error_handler();
 		if (!isset($_SESSION)) {
-			throw new \Exception('Failed to start session');
+			throw new \Exception('Failed to start session: "' . $error . '"');
 		}
 	}

The above patch should add some more information to the error message.

[kaipee]

I've added the patch, I'll keep an eye on the next error, thanks.