When we upgrade from 4.2 to higher version, documentations says agents are automatically installed. So when the agent connects to collector, does it download the latest version of the agent from internet? how does it get the latest software for the agents.
This is what documentation says-
from 4.2 and above: Java, .Net and Web Server Agents will be automatically installed by the Agent´s bootstrap part on connection to the Collector / Server.
Answer by Rob V. ·
You're right - it's not magic. When you upgrade your system (e.g. from 4.2 to 5.5) you would upgrade your dT infrastructure (server and collectors). At that point, the collector would have the updated agent binaries. As you surmised, when the agents attach to the updated collectors, the collector will push the new version of the agent.
You can see this on the monitored app server. In the directory that holds our agents you'll find a "downloads" directory that will have version-specfic core agents.
Answer by Ted F. ·
Let's say you upgrade from 4.2 to 5.5 (works with any version since 4.2, but just to use a specific version).
When the 4.2 Agent connects to the 5.5 Collector, it will get boostrapped to the 5.5. It will remain at version 4.2 and work fine until it is restarted at which point it will come up as a 5.5 agent.
Hope that helps...