Hello.
I am using AIX 6 and If wish to receive more than 500 files via SFTP, I get some time out errors. Could you please advise where is the limit for number of concurrent transfers setup in AIX Box or what is the limit and can that be changed?
Many Thanks
How many concurrent connections are you trying to establish to your AIX box? 500 all at one time? When you see the timeout errors, do you think it is because of an actual duration of time is being exceeded, your sshd is kicking you off, could it be a connection issue from the client side, or your sshd just isn't accepting enough connections? I'm pretty sure the sshd on AIX will not accept a large number of simultaneous connections at one time in an effort to protect itself from a DOS attack. It was previously discussed here:
http://www.unix.com/unix-advanced-expert-users/46982-max-numer-connections-per-sshd.html
Thanks for your reply. Yes 500 or may be more at a time. I want to know how many concurrent transfers can I kick off at single point of time? Yes, some of my transfer failed and its difficult to know which number of session made this trouble. Is there any way to find out the limitation or can I assume there is no limitation?
are your 500 files coming from 1 source or 500 ?
You can sftp with wildcards like
sftp mybox:/dumps/*dump* me@yourbox:/some/destinationdirectory/
and the likelyhood that this job will finish without issues is a lot higher than trying to transfer each file in its very own sftp process. You will overwhelm the recieve buffer who has to put the tcp ip pieces recieved together at the destination and as a result it will just reject anything it cannot handle.
4 sftp streams with 125 files each will be a lot more effective than 500 streams with one file each.
Regards
zxmaus