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Getting help
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The Basics
- Nextcloud Server version (e.g., 29.x.x):
33.0.2
- Operating system and version (e.g., Ubuntu 24.04):
Ubuntu 24.04
- Web server and version (e.g, Apache 2.4.25):
Apache 2.4.62
- PHP version (e.g, 8.3):
8.4
- Is this the first time you’ve seen this error? (Yes / No):
Yes
- When did this problem seem to first start?
NC 33.x
- Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
Bare Metal
- Are you using CloudfIare, mod_security, or similar? (Yes / No)
No
Summary of the issue you are facing:
The command
occ files:scan-app-data -v
is slow, provides no output and does not return.
The command cannot be interrupted with CTRL+C
Steps to replicate it (hint: details matter!):
After upgrading to NC 33.x, I have executed
occ preview:cleanup
occ preview:generate-all
to migrate all previews to the new architecture.
However, after all previews have been regenerated, I saw errors like
[index] Fehler: Unable to open preview stream at <nc-path>/appdata_oca547gxxkcm/preview/5/d/c/e/f/3/9/12431/256-455.jpg
GET /index.php/core/preview?fileId=12431&x=256&y=256&a=1&mode=cover&forceIcon=0
von 192.168.178.34 von <user> um 04.04.2026, 11:58:02
So I thought that rescanning app data would fix this issue. So, I execute
occ files:scan-app-data
Which prints
Scanning AppData for files
and then nothing else. I cannot interrupt the command with CTRL+C. It is like the terminal window is stuck.
I have run this command in a background process for over 3 days and it did not finish. I saw mariadb taking ~25-50% CPU load the whole time with some gs (ghostscript?) every now and then.
I have enabled slow queries log in MariaDB, but there is nothing in the log.
There is also nothing the normal MariaDB Log
Log entries
Nextcloud
Please provide the log entries from your Nextcloud log that are generated during the time of problem (via the Copy raw option from Administration settings->Logging screen or from your nextcloud.log located in your data directory). Feel free to use a pastebin/gist service if necessary.
None
Configuration
Nextcloud
The output of occ config:list system or similar is best, but, if not possible, the contents of your config.php file from /path/to/nextcloud is fine (make sure to remove any identifiable information!):
{
"system": {
"serverid": 0,
"default_phone_region": "DE",
"onlyoffice": {
"editors_check_interval": 0,
"verify_peer_off": true,
"jwt_header": "AuthorizationJwt",
"jwt_secret": "***REMOVED SENSITIVE VALUE***"
},
"instanceid": "***REMOVED SENSITIVE VALUE***",
"passwordsalt": "***REMOVED SENSITIVE VALUE***",
"secret": "***REMOVED SENSITIVE VALUE***",
"forwarded_for_headers": [
"HTTP_X_FORWARDED"
],
"trusted_proxies": "***REMOVED SENSITIVE VALUE***",
"trusted_domains": [
"192.168.178.3",
"***REMOVED SENSITIVE VALUE***",
"127.0.0.1",
"***REMOVED SENSITIVE VALUE***",
"***REMOVED SENSITIVE VALUE***"
],
"allowed_admin_ranges": [
"192.168.0.0\/16"
],
"datadirectory": "***REMOVED SENSITIVE VALUE***",
"dbtype": "mysql",
"version": "33.0.2.2",
"overwrite.cli.url": "***REMOVED SENSITIVE VALUE***",
"dbname": "***REMOVED SENSITIVE VALUE***",
"dbhost": "***REMOVED SENSITIVE VALUE***",
"dbport": "",
"dbtableprefix": "oc_",
"mysql.utf8mb4": true,
"dbuser": "***REMOVED SENSITIVE VALUE***",
"dbpassword": "***REMOVED SENSITIVE VALUE***",
"installed": true,
"mail_smtpmode": "smtp",
"mail_sendmailmode": "smtp",
"mail_smtpauthtype": "LOGIN",
"mail_smtphost": "***REMOVED SENSITIVE VALUE***",
"mail_smtpport": "587",
"mail_smtpauth": true,
"mail_smtpname": "***REMOVED SENSITIVE VALUE***",
"mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
"mail_from_address": "***REMOVED SENSITIVE VALUE***",
"mail_domain": "***REMOVED SENSITIVE VALUE***",
"memcache.local": "\\OC\\Memcache\\APCu",
"memcache.distributed": "\\OC\\Memcache\\Redis",
"memcache.locking": "\\OC\\Memcache\\Redis",
"redis": {
"host": "***REMOVED SENSITIVE VALUE***",
"port": 0
},
"enabledPreviewProviders": [
"OC\\Preview\\PNG",
"OC\\Preview\\JPEG",
"OC\\Preview\\GIF",
"OC\\Preview\\HEIC",
"OC\\Preview\\BMP",
"OC\\Preview\\MP3",
"OC\\Preview\\TXT",
"OC\\Preview\\PDF",
"OC\\Preview\\MP4",
"OC\\Preview\\MarkDown",
"OC\\Preview\\MOV",
"OC\\Preview\\Image",
"OC\\Preview\\TIFF",
"OC\\Preview\\Movie"
],
"preview_max_x": 2560,
"preview_max_y": 1440,
"jpeg_quality": 90,
"maintenance": false,
"data-fingerprint": "30b96630ec3d1182ae55146a72cb7777",
"theme": "",
"htaccess.RewriteBase": "\/",
"loglevel": 2,
"updater.release.channel": "stable",
"ncd_admin_settings": {
"disallow_aria2_settings": "0",
"ncd_yt_binary": "",
"ncd_aria2_binary": ""
},
"allow_local_remote_servers": true,
"maintenance_window_start": "2",
"defaultapp": "",
"trashbin_retention_obligation": "15,30",
"memories.exiftool": "\/var\/www\/nextcloud\/apps\/memories\/bin-ext\/exiftool-amd64-glibc",
"memories.vod.path": "\/var\/www\/nextcloud\/apps\/memories\/bin-ext\/go-vod-amd64",
"memories.vod.ffmpeg": "\/usr\/bin\/ffmpeg",
"memories.vod.ffprobe": "\/usr\/bin\/ffprobe",
"memories.gis_type": 1,
"memories.db.triggers.fcu": true,
"app_install_overwrite": {
"0": "unsplash",
"1": "co2clock",
"3": "files_downloadactivity",
"4": "otpmanager"
},
"log.condition": {
"apps": [
"admin_audit"
]
},
"logfile_audit": "\/media\/Samsung4TB\/nextcloud_data\/nextcloud.log",
"music.lastfm_api_key": "***REMOVED SENSITIVE VALUE***",
"files.chunked_upload.max_size": 5242880,
"forbidden_filename_basenames": [
"con",
"prn",
"aux",
"nul",
"com0",
"com1",
"com2",
"com3",
"com4",
"com5",
"com6",
"com7",
"com8",
"com9",
"com\u00b9",
"com\u00b2",
"com\u00b3",
"lpt0",
"lpt1",
"lpt2",
"lpt3",
"lpt4",
"lpt5",
"lpt6",
"lpt7",
"lpt8",
"lpt9",
"lpt\u00b9",
"lpt\u00b2",
"lpt\u00b3"
],
"forbidden_filename_characters": [
"<",
">",
":",
"\"",
"|",
"?",
"*",
"\\",
"\/"
],
"forbidden_filename_extensions": [
" ",
".",
".filepart",
".part"
],
"memories.vod.vaapi": true,
"memories.vod.disable": false,
"memories.vod.use_transpose": true
}
}
Apps
The output of occ app:list (if possible).
Enabled:
- admin_audit: 1.23.0
- app_api: 33.0.0
- bruteforcesettings: 6.0.0
- calendar: 6.2.2
- cloud_federation_api: 1.17.0
- contacts: 8.4.3
- dashboard: 7.13.0
- dav: 1.36.0
- epubviewer: 1.9.2
- federatedfilesharing: 1.23.0
- files: 2.5.0
- files_antivirus: 6.2.0
- files_pdfviewer: 6.0.0
- files_sharing: 1.25.2
- files_trashbin: 1.23.0
- impersonate: 4.0.0
- integration_paperless: 1.0.11
- logreader: 6.0.0
- lookup_server_connector: 1.21.0
- memories: 8.0.1
- music: 3.0.0
- notes: 4.13.1
- notifications: 6.0.0
- notify_push: 1.3.1
- oauth2: 1.21.0
- onlyoffice: 10.0.0
- otpmanager: 1.1.2
- password_policy: 5.0.0
- passwords: 2026.3.21
- photos: 6.0.0
- previewgenerator: 5.13.0
- privacy: 5.0.0
- profile: 1.2.0
- provisioning_api: 1.23.0
- recognize: 11.0.1
- related_resources: 4.0.0
- serverinfo: 5.0.0
- settings: 1.16.0
- sharebymail: 1.23.0
- sharereview: 2.1.0
- side_menu: 5.3.0
- spreed: 23.0.3
- systemtags: 1.23.0
- tasks: 0.17.1
- text: 7.0.0
- theming: 2.8.0
- theming_customcss: 1.20.0
- twofactor_backupcodes: 1.22.0
- twofactor_totp: 15.0.0
- unsplash: 3.1.0
- updatenotification: 1.23.0
- viewer: 6.0.0
- weather_status: 1.13.0
- webhook_listeners: 1.5.0
- workflow_script: 4.0.0
- workflowengine: 2.15.0
Disabled:
- activity: 6.0.0 (installed 2.15.0)
- circles: 33.0.0 (installed 23.1.0)
- comments: 1.23.0 (installed 1.14.0)
- contactsinteraction: 1.14.1 (installed 1.6.0)
- encryption: 2.21.0
- federation: 1.23.0 (installed 1.14.0)
- files_downloadlimit: 5.1.0 (installed 5.0.0-dev.0)
- files_external: 1.25.1
- files_reminders: 1.6.0 (installed 1.5.0)
- files_versions: 1.26.0 (installed 1.18.0)
- firstrunwizard: 6.0.0 (installed 2.13.0)
- nextcloud_announcements: 5.0.0 (installed 1.16.0)
- recommendations: 6.0.0 (installed 1.2.0)
- support: 5.0.0 (installed 1.10.0)
- survey_client: 5.0.0 (installed 1.10.0)
- suspicious_login: 11.0.0 (installed 4.4.0)
- testing: 1.23.0
- twofactor_nextcloud_notification: 7.0.0
- user_ldap: 1.24.0
- user_status: 1.13.0 (installed 1.2.0)