SUMMARY
The Apple iCal client is particular about connecting to CalDAV and CardDAV servers (in that it typically requires the correct configuration of DNS infrastructure). It often does not give meaningful errors when it is unable to connect to backend CalDAV servers.
To avoid connectivity issues, it is important that you have correctly configured SRV DNS records for the domains offering these services.
This document explains how to configure DNS and then configure an iCal client.
CONFIGURING DNS INFRASTRUCTUREWhen deploying CalDAV and CardDAV services, it is strongly recommended that you configure DNS records to allow clients to locate and connect to these services. This involves creating specific SRV DNS records so that they are published to clients.
For CalDAV you should configure the following SRV records :
Example: service record for server without transport layer security
_caldav._tcp SRV 0 1 8008 example.com.
Example: service record for server with transport layer security
_caldavs._tcp SRV 0 1 8443 example.com.
Note: In the above example, you should also have a DNS A (Host) record created that equates "example.com" to an IP address.
More information can be found at:
http://tools.ietf.org/html/draft-daboo-srv-caldav-10
Important: The Apple iCal client will use Port 8443 by default. If you are having issues connecting from an iCal client, it is suggested that you consider running the server on port 8443 for SSL and 8008 for Non-SSL. You should not use the port number for _caldavs as and _caldav.
CONFIGURING AN ICAL CLIENT
To set up a iCal to connect via CalDAV, please follow these steps.
1. Launch the iCal application
2. Under the iCal menu, select Preferences..
3. Click Accounts
4. Click + to add a new account
5. Set the Account type as CalDAV
6. Specify the username and password
7. Enter the server address as the domain name that is hosts the SRV records for CalDAV (see earlier section on configuring DNS infrastructure). In the case of the example provided, this would be "example.com".
8. You should then click the Create button. Once this is clicked, the iCal client will query DNS for example.com and identify the appropriate SRV record. It will use this record to identify the host and port number that is will then connect to.
MANUALLY CONFIGURING AN ICAL CLIENT
If your initial connection fails, then you can continue and enter manual settings under "Calendar Server Options", following these steps:
1. From the account template, select "iCal Server"
2. Re-enter your username and password as desired.
3. For the server address, specify the IP address or hostname of the server running CalDAV.
4. Leave the Server path as /calendar (for versions post MailEnable 5.10 you can leave the path as /principals/users/[username]/)
5. Specify the desired port Number (eg: 8443) and tick whether or not SSL is configured for this port (uncheck Kerberos Authentication).
6. Click Create to attempt to connect with the CalDAV server.
MORE INFORMATIONMore information can be found at:
http://tools.ietf.org/html/draft-daboo-srv-caldav-10
Apple also provides the following article:
http://docs.info.apple.com/article.html?path=ServerAdmin/10.6/en/cs4d72c0a5.html