Is there a way to suppress a message from the log buffer, but still send it to the syslog server?

Enable NETCONF on the router and do, $ ssh user@hostname -p 830 -s netconf

By the way, this is not the way IOS XR works, it uses PIEs and SMUs.You add/remove or activate/deactivate PIEs/SMUs, you do not delete files in the filesystem on your own.By looking through your files just now, I see that you are already affected by ...

At the moment there are issues with upgrading from 4.2.0 to 4.2.1, if you run the "install verify packages" it will fail due to missing files. The recommendation is to turboboot the 4.2.1 if you really want to use IOS XR 4.2.1, otherwise stay at 4.2....