Recreating a Self-Signed SSL Certificate in ZCS 4.5 & 5.0
- 1 Self Signed Certificate Instructions
- 1.1 Back up existing certificates
- 1.2 Delete and re-create SSL Directory (as root)
- 1.3 Give the zimbra user write access to the cacerts keystore
- 1.4 Remove the self-signed root certificate from the cacerts keystore (as zimbra)
- 1.5 Delete the server cert from the tomcat keystore (as zimbra)
- 1.6 Perform optional configuration
- 1.7 Create the CA certificate (as zimbra)
- 1.8 Install server ca files
- 1.9 Create the server certificate (as zimbra)
- 1.10 Install the server certificate files (as zimbra)
- 1.11 Restart zimbra services
- 2 Note about 'unable to write random state'
Self Signed Certificate Instructions
If you're working with a commercial certificate, do *NOT* use this page - go here instead
- To clean up SSL certificates and recreate a new self-signed cert try this.
Back up existing certificates
- This backs up the default certificates created by zmcreateca and zmcreatecert:
tar cf /tmp/zimbra-ssl-bak.tar /opt/zimbra/ssl/
- This backs up the server's working certificate files:
cd /opt/zimbra/ tar cf /tmp/zimbra-certs.tar conf/ca/ conf/*.crt conf/*.key conf/*.pem tomcat/conf/keystore java/jre/lib/security/cacerts
Delete and re-create SSL Directory (as root)
su - rm -rf /opt/zimbra/ssl mkdir /opt/zimbra/ssl chown zimbra:zimbra /opt/zimbra/ssl
Give the zimbra user write access to the cacerts keystore
- On linux the java cacerts file is a part of the ZCS installation.
chown zimbra:zimbra /opt/zimbra/java/jre/lib/security/cacerts chmod 644 /opt/zimbra/java/jre/lib/security/cacerts
- On Mac OS X the java cacerts file is a part of the system's java installation. Either run the "keytool -delete ..." command in the next section as root or give write access to the zimbra user.
chown zimbra:zimbra /System/Library/Frameworks/JavaVM.framework/Versions/1.5/Home/lib/security/cacerts chmod u+w /System/Library/Frameworks/JavaVM.framework/Versions/1.5/Home/lib/security/cacerts
Remove the self-signed root certificate from the cacerts keystore (as zimbra)
- Mac OS X
keytool -delete -alias my_ca -keystore /System/Library/Frameworks/JavaVM.framework/Versions/1.5/Home/lib/security/cacerts -storepass changeit
keytool -delete -alias my_ca -keystore /opt/zimbra/java/jre/lib/security/cacerts -storepass changeit
Delete the server cert from the tomcat keystore (as zimbra)
su - zimbra keytool -delete -alias tomcat -keystore /opt/zimbra/tomcat/conf/keystore -storepass zimbra
Perform optional configuration
- If you want to change the duration of the certificate from the default (365 days), modify the "default_days" entry in the file /opt/zimbra/conf/zmssl.cnf.in
Workaround: zmssl.cnf.in default_days is ingnored. Currently you will need to edit zmcreateca and zmcreatecert: Bug is http://bugzilla.zimbra.com/show_bug.cgi?id=12228
- If you want the common name show up in the CA rather than 'Zimbra Collaboration Suite' because you have several zimbra servers. Please Note: I probably have unnecessary steps in this section here, but this is what I did to get it working for me.
vi /opt/zimbra/conf/zmssl.cnf.in [change section to appear as below] 0.organizationName = Zimbra 0.organizationName_default = Zimbra # we can do this but it is not needed normally :-) #1.organizationName = Second Organization Name (eg, company) #1.organizationName_default = World Wide Web Pty Ltd organizationalUnitName = Zimbra organizationalUnitName_default = Zimbra commonName = <put your hostname here -- @@HOSTNAME@@ doesn't seem to work> commonName_max = 64 commonName_default = <put your hostname here -- @@HOSTNAME@@ doesn't seem to work>
Create the CA certificate (as zimbra)
- (OPTIONAL) If you did the Optional step to make the CN the hostname for the CA, the output should be like the following:
... Signature ok subject=/C=US/ST=N/A/L=N/A/O=Zimbra/OU=Zimbra/CN=<your hostname> Getting Private key unable to write 'random state'
Install server ca files
- After creating the ca, it appears that zmcreateca doesn't copy the new ca.key and ca.pem to /opt/zimbra/conf/ca, so do it manually (as zimbra):
cp /opt/zimbra/ssl/ssl/ca/ca.key /opt/zimbra/conf/ca/ca.key cp /opt/zimbra/ssl/ssl/ca/ca.pem /opt/zimbra/conf/ca/ca.pem
Create the server certificate (as zimbra)
Install the server certificate files (as zimbra)
zmcertinstall mailbox /opt/zimbra/ssl/ssl/server/tomcat.crt zmcertinstall mta /opt/zimbra/ssl/ssl/server/server.crt /opt/zimbra/ssl/ssl/server/server.key
- I don't know what the CA cert stored in LDAP is used for, or if it is used at all, but it is *not* updated by the above steps. To update CA cert (as zimbra):
cat /opt/zimbra/ssl/ssl/ca/ca.key zmprov -l mcf zimbraCertAuthorityKeySelfSigned "-----BEGIN RSA PRIVATE KEY----- [paste the contents of ca.key from above - I needed to construct this whole command in a text editor then paste into the CLI] -----END RSA PRIVATE KEY-----"
cat /opt/zimbra/ssl/ssl/ca/ca.pem zmprov -l mcf zimbraCertAuthorityCertSelfSigned "-----BEGIN TRUSTED CERTIFICATE----- [paste the contents of ca.pem from above - I needed to construct this whole command in a text editor then paste into the CLI] -----END TRUSTED CERTIFICATE-----"
- You can see your updated certs in LDAP now and compare them to contents of /opt/zimbra/ssl/ssl/ca (as zimbra)
zmprov -l gcf zimbraCertAuthorityKeySelfSigned zmprov -l gcf zimbraCertAuthorityCertSelfSigned
Restart zimbra services
- It may be necessary to restart the Zimbra servers for the changes to take effect (as zimbra).
zmcontrol stop zmcontrol start