Setting Java DNS cache TTL
dns, java
Solution
These are not system properties: they are set in the java.security file. For the corresponding system properties, which are non-preferred, see 'Sun implementation-specific properties' in Networking Properties.
Problem
I'm attempting to change the DNS cache timeout in Java 1.6. I see discussion here of using something like the following: ``` java.security.Security.setProperty ("networkaddress.cache.ttl" , TTL_SECS); ``` But I've tried this simple test in Win 7.... ``` System.out.println("DEFAULT DNS TTL: "+sun.net.InetAddressCachePolicy.get()); java.security.Security.setProperty ("networkaddress.cache.ttl" , "123"); System.out.println("DEFAULT DNS TTL: "+sun.net.InetAddressCachePolicy.get()); ``` ... and the output doesn't change. It seems this can be changed in the Java installation's security properties but I preffer to keep this in the code for neatness. Any ideas how to achieve that? Thanks.