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I've modified the IdP's log rotation behavior to use a fixed window appender and gzip logs by default:
http://logback.qos.ch/manual/appenders.html
This should also cap the IdP's logs at less than 675MB(gzipped) per node, which I think is pretty generous. I'll crop it down further if necessary. I'll look into something similar for Tomcat once that transition is done. I don't know of any system services that involve perpetual logs, so that might be the extent of it on the IdP VM's.
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