RSH scaling problems...

Greg Lindahl lindahl at
Tue Dec 17 08:42:35 PST 2002

On Tue, Dec 17, 2002 at 06:09:07AM -0500, Jeff Layton wrote:

>    So, even if you patch the kernel to give you more than 256 ptys,
> you also need to patch rcmd() to use a wider range of ports (at least
> in theory).
>    Any comments?

rcmd must use low ports, for security reasons.

ssh has a mode in which it can use a high port. That's how the
370-node FSL system did it in 1999. This technique also worked OK on
Cplant at 1200 nodes.

-- greg

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