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- Copy disable-writes.xml (see below) into your $FEDORA_HOME/data/fedora-xacml-policies/repository-policies/default/directory
- Run $FEDORA_HOME/server/bin/fedora-reload-policies.sh http reloadpolicies https admin-user admin-pass (this immediately makes any repo-wide policy changes active without requiring a restart; change https to http if your server only supports http)
- Wait a few minutes to let any in-progress writes complete.
- Do a database+filesystem backup (see this page for the files involved)
- Remove disable-writes.xml
- Run fedora-reload-policies again
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