Questions[limitations](server)

I recall reading this in some (I think) Cisco documentation years ago, but can't find it or any other reference to this recommendation.

Anyone know what I'm talking about? Anyone still follow these guidelines? I'm generally a "wasteful" subnetter using /24s almost exclusively (except for point-to-point links between routers and also DMZs) so I'm well below the "maximum", but I'm just curious as to this limitation and whether it was based on some old benchmarks having to do with broadcast traffic, etc.

Does Windows Server 2008 R2 have similar limitations to maximum number of opened files like linux have?

I know that Yahoo and Google mail support 25MB email attachments. I have an idea from somewhere that 10MB email messages are generally supported by modern email systems.

So if I'm sending an email between two arbitrary users on the internet, what's the safe upper bound on message size? 1MB? 10MB? 25MB?

I know that one answer is 'don't send big emails, use some sort of drop box'. I'm looking for a guideline if you are limited to only using regular smtp email.

silly one,

do you have any problems with rsync'ing large [ >4GB ] files under modern linux? [ 32bit, 64bit, large file support turned on ]? i've done some tests on my own between 2 64bit boxes and didn't have any problems transferring 6-10GB files. to make test thorough i altered files, run rsync again, checked md5... - all seems ok.

but after i saw this bug report i got a bit worried. i did some searching but have not found any confirmation of the problem.

thanks for your thoughts!

edit: file system: ext3, reiserfs

I am using CentOS 5 with Plesk 9 (64-bit), I am running a site where users will be uploading pictures. With a 64 bit os, are there any limits to how many files I can store? All I care about is performance, and serving up the files. I'd prefer not to have 4 directories deep of scattered files. However, I am hoping, that at some point I could have 200-300 thousand images.