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On this intranet system, I have about 100 incoming SFTP jobs that start running at the same time, and which regularly hit the MaxStartups default of 10.

Of course, according to the owner of the SFTP jobs, chronological distribution of the jobs is totally impossible and entirely out of the question. I therefore wonder what experience you might have with raising MaxStartups significantly to a value of 50, 100 or 200.

Will the server be able to handle that many simultaneous authentications? I have no experience with that amount of concurrency on SSH.

The server is of course current hardware. 8 CPU cores @2.13GHz and 4 GB RAM.

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You failed to mention anything about your server hardware. Commodore 64? Amiga 500? 386SX? Something decent, such as some actual server hardware from HP/Dell/whatever? – Janne Pikkarainen Nov 23 '11 at 12:53
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Should work OK, I guess network bandwidth might be the bottleneck. Try it! Raise the value first to 50, let it run, see if it works. If there are no problems, raise the value again to 100, let it run, see if it works. Repeat until satisfied.

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I tried it and won't say that the server collapses under 200 concurrent SSH session initiations. Nevertheless, the spike in CPU utilization is sufficiently ugly to keep defending MaxStartups 10 for a while. – unixtippse Nov 30 '11 at 12:56

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