I run a couple of gentoo openmosix SSI clusters (read: lots of machines) and I've noticed that uptime is not limited by software stability, but rather by hardware failure / upgrades, changing server rooms, severe system updates (mainly kernel changes), and the likes. Once the machines are left alone, they happily keep humming away into hundreds of days.
And to answer your real question, It's generally not a problem to upgrade gentoo in the background. A package here, a package there whenever you've got the time. Sometimes I've run into serious problems, such as the KDE update from hell, but even that could be done in the background on the production machines, once I've tried it out on my home box. The major update problem I'd say is the kernel. It would be nice to be able to transfer running user space images between kernels. Jimmy CSOL research -- [EMAIL PROTECTED] mailing list
