FTP Transfers over 1MB fail

[Michael Zayti]

Hopefully i will be able to gain some insight into this problem here. The office has a number of Visualize c3600 boxes that run HP-UX. all run flawlessly with the exception of one. while uploading to this machine from another on the same network, files over 1-2MB in size time out, and the c3600 closes the connection, does anyone have an idea of what may be causing this. (NOTE: this machine is a server)

any help would be greatly appreciated.

[Mark Greene_1 · Accepted solution]

Are you running out of space or inodes in the file system where you are ftp'ing the file?

(been there, had that happen to me more than once!)


mark

[John Poff]

Hi,

I've seen some similar things happen when the speed and/or duplex of the LAN card was mismatched with the setting on the other end.

JP

[Michael Zayti]

i dont believe space is an issue, almost positive that we have more than enough head room. youl have to excuse my ignorance on the "inodes", what are they, how do i check for a possible issue with them?

[Mark Greene_1]

run "bdf ." in the filesystem where the file is being transfered to. The inodes are the number of files that a file system can contain, and has to be preconfigured at the time of the file system creation.

This used to be an administrative issue when system limits were small due to the limitations imposed by 8- and 16-bit systems. 32-bit systems gave use doube-wide integers (if I'm recalling this correctly) and correspondingly larger numbers to set limits to.

[Michael Zayti]

okay, does not sound insanely difficult, i will definately check into that, thank you very much!

[Dave Olker]

Hi Michael,

I'd be pretty surprised if an inode problem manifested itself by not allowing files of a certain size to transfer. If you run out of inodes in the filesystem, you won't be able to add any files to the filesystem - regardless of size. Also, this is only really applicable to HFS filesystems, since VxFS filesystems add inodes dynamically when they run out.

This sounds like a networking problem of some kind. My suggestion would be to collect a network trace of a "working" file transfer session and a "failing" file transfer session and analyze the traces to see why the connection is shutting down during the failing case. Are packets being sent to the server that don't get acknowledged? Is the server sending a RST on the connection? etc.

The results of analyzing the network traces will hopefully give you an idea what is causing the connection to close, or at least point you in the direction of where to look next.

Regards,

Dave

[Michael Zayti]

Well, after some exhaustive reading of a few dozen manuals...here was the solution to the problem. Yurns out this "quenching" setting can be a rather troublesome lil bugger. thanks to everyone for their kind help. maybe this fix will help someone later.


You can disable source quench in HP-UX 11.0 by executing this command:

ndd -set /dev/ip ip_send_source_quench 0

To disable Source Quench so that it can survive a reboot, modify the /etc/rc.config.d/nddconf file as follows :

TRANSPORT_NAME[X]=ip
NDD_NAME[X]=ip_send_source_quench
NDD_VALUE[X]=0

Where X is the next logical numerical sequence in a table of values, with X starting at 0.