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Sorry to hear you’re facing problems 
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example
Or for longer, use three backticks above and below the code snippet:
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Nextcloud version (eg, 18.0.2):
Operating system and version (eg, Ubuntu 20.04):
Apache or nginx version (eg, Apache 2.4.25):
PHP version (eg, 7.1):
The issue you are facing:
I get error while trying connecting from an external domain, but only after there is no one connected to the website and after a while. To make it accessible again I have to connect with local ip address and then the domain starts working again.
Is this the first time you’ve seen this error? (Y/N): N
Steps to replicate it:
- disconnect from website
- wait a while
- try to connect from external ip or domain
The output of your Nextcloud log in Admin > Logging:
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:36+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:36+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:36+0100
Fatal webdav Sabre\DAV\Exception: Could not rename part file to final file
2020-12-16T15:25:36+0100
Error webdav renaming part file to final file failed $renameOkay: false, $fileExists: false)
2020-12-16T15:25:36+0100
Error core unable to rename, source directory is not writable : uploads/web-file-upload-c98bc7f0f88b247c702cce60ee3307a6-1608128675433
2020-12-16T15:25:36+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:35+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:35+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:35+0100
Fatal webdav Sabre\DAV\Exception: Could not rename part file to final file
2020-12-16T15:25:35+0100
Error webdav renaming part file to final file failed $renameOkay: false, $fileExists: false)
2020-12-16T15:25:35+0100
Error core unable to rename, source directory is not writable : uploads/web-file-upload-10218b8a17d2fa517b32c5058e053e74-1608128675434
2020-12-16T15:25:35+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:30+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:30+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:30+0100
Fatal webdav Sabre\DAV\Exception: Could not rename part file to final file
2020-12-16T15:25:30+0100
Error webdav renaming part file to final file failed $renameOkay: false, $fileExists: false)
2020-12-16T15:25:30+0100
Error core unable to rename, source directory is not writable : uploads/web-file-upload-a5f87a6957d6f8108f6b6978498b8390-1608128675427
2020-12-16T15:25:30+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:29+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:29+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:25:29+0100
Fatal webdav Sabre\DAV\Exception: Could not rename part file to final file
2020-12-16T15:25:29+0100
Error webdav renaming part file to final file failed $renameOkay: false, $fileExists: false)
2020-12-16T15:25:29+0100
Error core unable to rename, source directory is not writable : uploads/web-file-upload-dc8adb28594c9e865388c422dee441dc-1608128675432
2020-12-16T15:25:29+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:24:47+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:24:47+0100
Error PHP Error: Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#691
2020-12-16T15:24:47+0100
Error no app in context Sabre\DAV\Exception\BadRequest: Expected filesize of 7816395 bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) 4947968 bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
PASTE HERE
<?php
$CONFIG = array (
'instanceid' => 'ocs8df9n9ty9',
'passwordsalt' => '+',
'secret' => '+',
'trusted_domains' =>
array (
0 => 'xx.xx.xx.xx',
1 => '192.168.1.54',
2 => 'my.domain',
),
'datadirectory' => '/var/nextdata/data',
'dbtype' => 'sqlite3',
'version' => '20.0.4.0',
'overwrite.cli.url' => 'http://my.domain/nextcloud',
'installed' => true,
'mail_smtpmode' => 'smtp',
'mail_smtpauthtype' => 'LOGIN',
'mail_sendmailmode' => 'smtp',
'mail_smtpauth' => 1,
'mail_smtphost' => 'smtp.gmail.com',
'mail_smtpport' => '25',
'mail_from_address' => 'my.domain',
'mail_domain' => 'gmail.com',
'mail_smtpname' => 'xxxx@xxxx.xxx',
'mail_smtppassword' => 'xxxx',
'mail_smtpsecure' => 'tls',
'log_type' => 'errorlog',
'maintenance' => false,
);
The output of your Apache/nginx/system log in `/var/log/____`:
[Fri Dec 18 00:00:08.298665 2020] [ssl:warn] [pid 684] AH01906: 127.0.1.1:443:0 server certificate is a CA certificate (BasicConstraints: CA == TRUE !?)
[Fri Dec 18 00:00:08.298791 2020] [ssl:warn] [pid 684] AH01909: 127.0.1.1:443:0 server certificate does NOT include an ID which matches the server name
[Fri Dec 18 00:00:08.299266 2020] [mpm_prefork:notice] [pid 684] AH00163: Apache/2.4.38 (Raspbian) OpenSSL/1.1.1d configured – resuming normal operations
[Fri Dec 18 00:00:08.299289 2020] [core:notice] [pid 684] AH00094: Command line: ‘/usr/sbin/apache2’
[Fri Dec 18 07:19:07.151937 2020] [php7:notice] [pid 3101] [client 93.xx.xx.xx:38692] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of$
[Fri Dec 18 07:45:50.982775 2020] [php7:notice] [pid 5485] [client 151.28.211.114:36100] [owncloud][PHP][3] {“Exception”:“Error”,“Message”:"Illegal string offse$
[Fri Dec 18 07:46:16.449973 2020] [php7:notice] [pid 5504] [client 151.28.211.114:36120] [owncloud][PHP][3] {“Exception”:“Error”,“Message”:"Illegal string offse$
[Fri Dec 18 07:51:57.505284 2020] [php7:notice] [pid 5484] [client 93.xx.xx.xx:38960] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of$
cat: /sys/class/net/wlan0/speed: Invalid argument
cat: /sys/class/net/wlan0/duplex: Invalid argument
[Fri Dec 18 08:37:16.783411 2020] [php7:notice] [pid 5504] [client 192.168.1.55:34516] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of $
[Fri Dec 18 08:43:23.289965 2020] [php7:notice] [pid 5644] [client xx.xx.xx.xx:40366] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of$
cat: /sys/class/net/wlan0/speed: Invalid argument
cat: /sys/class/net/wlan0/duplex: Invalid argument
[Fri Dec 18 08:53:15.660519 2020] [mpm_prefork:notice] [pid 684] AH00169: caught SIGTERM, shutting down
[Fri Dec 18 08:53:34.452319 2020] [ssl:warn] [pid 636] AH01906: 127.0.1.1:443:0 server certificate is a CA certificate (BasicConstraints: CA == TRUE !?)
[Fri Dec 18 08:53:34.460809 2020] [ssl:warn] [pid 636] AH01909: 127.0.1.1:443:0 server certificate does NOT include an ID which matches the server name
[Fri Dec 18 08:53:36.046624 2020] [ssl:warn] [pid 683] AH01906: 127.0.1.1:443:0 server certificate is a CA certificate (BasicConstraints: CA == TRUE !?)
[Fri Dec 18 08:53:36.046740 2020] [ssl:warn] [pid 683] AH01909: 127.0.1.1:443:0 server certificate does NOT include an ID which matches the server name
[Fri Dec 18 08:53:36.094434 2020] [mpm_prefork:notice] [pid 683] AH00163: Apache/2.4.38 (Raspbian) OpenSSL/1.1.1d configured – resuming normal operations
[Fri Dec 18 08:53:36.094605 2020] [core:notice] [pid 683] AH00094: Command line: ‘/usr/sbin/apache2’
cat: /sys/class/net/wlan0/speed: Invalid argument
cat: /sys/class/net/wlan0/duplex: Invalid argument
cat: /sys/class/net/wlan0/speed: Invalid argument
cat: /sys/class/net/wlan0/duplex: Invalid argument
[Fri Dec 18 09:12:49.795091 2020] [php7:notice] [pid 2610] [client xx.xx.xx.xx:41032] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of$
[Fri Dec 18 09:32:05.720396 2020] [php7:notice] [pid 2611] [client xx.xx.xx.xx:41104] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of$
[Fri Dec 18 10:39:12.244659 2020] [php7:notice] [pid 2721] [client 192.168.1.55:35900] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of $
cat: /sys/class/net/wlan0/speed: Invalid argument
cat: /sys/class/net/wlan0/duplex: Invalid argument
cat: /sys/class/net/wlan0/speed: Invalid argument
cat: /sys/class/net/wlan0/duplex: Invalid argument
[Fri Dec 18 11:04:14.860547 2020] [php7:notice] [pid 755] [client 192.168.1.55:37052] [owncloud][index][3] {“Exception”:“Exception”,“Message”:"Return value of O$