Provided by: ca-certificates_20241223_all 

NAME
update-ca-certificates - update /etc/ssl/certs and ca-certificates.crt
SYNOPSIS
update-ca-certificates [options]
DESCRIPTION
This manual page documents briefly the update-ca-certificates command.
update-ca-certificates is a program that manages the collection of TLS certificates for the local machine
and generates ca-certificates.crt. ca-certificates.crt is a single-file of concatenated certificates.
The collection of individual certificates is stored at /etc/ssl/certs.
The program reads the configuration file /etc/ca-certificates.conf. Each line gives a pathname of a CA
certificate under /usr/share/ca-certificates that should be trusted. Lines that begin with "#" are
comment lines and thus ignored. Lines that begin with "!" are deselected, causing the deactivation of
the CA certificate in question.
Certificates must be in PEM format and have a .crt extension in order to be included by update-ca-
certificates. Furthermore, all certificates with a .crt extension found below /usr/local/share/ca-
certificates are also included and implicitly trusted.
To add one or more certificates to the machine, copy the certificates in PEM format with the *.crt
extension to /usr/local/share/ca-certificates. There should be one certificate per file, and not multiple
certificates in a single file. Then run update-ca-certificates to merge the new certificates into the
existing machine store at /etc/ssl/certs.
Before terminating, update-ca-certificates invokes run-parts on /etc/ca-certificates/update.d and calls
each hook with a list of certificates: those added are prefixed with a +, those removed are prefixed with
a -.
OPTIONS
A summary of options is included below.
-h, --help
Show summary of options.
-v, --verbose
Be verbose. Output openssl rehash.
-f, --fresh
Fresh updates. Remove symlinks in /etc/ssl/certs directory.
--certsconf
Change the configuration file. By default, the file /etc/ca-certificates.conf is used.
--certsdir
Change the certificate directory. By default, the directory /usr/share/ca-certificates is used.
--localcertsdir
Change the local certificate directory. By default, the directory /usr/local/share/ca-certificates
is used.
--etccertsdir
Change the /etc certificate directory. By default, the directory /etc/ssl/certs is used.
FILES
/etc/ca-certificates.conf
A configuration file.
/etc/ssl/certs/ca-certificates.crt
A single-file version of CA certificates. This holds all CA certificates that were activated in
/etc/ca-certificates.conf.
/usr/share/ca-certificates
Directory of CA certificates provided by the distribution.
/usr/local/share/ca-certificates
Directory of local CA certificates, with .crt extension, provided by the user.
SEE ALSO
openssl(1)
AUTHOR
This manual page was written by Fumitoshi UKAI <ukai@debian.or.jp>, for the Debian project (but may be
used by others).
20 April 2003 UPDATE-CA-CERTIFICATES(8)