topic Re: ftp/server problem in Operating System - Linux

ftp/server problem

joseph wholey — Mon, 24 Dec 2007 17:29:38 GMT

For network benchmarking purposes, I'm attempting to ftp data from AIX5.3 to a RHEL4 Linux server. Below is the command as well as the message I recieve:

put "|dd if=/dev/zero bs=32k count=10000" /dev/null

dd: 0511-053 The write failed.
: There is no process to read data written to a pipe.
wait: There are no child processes.

Any ideas? Again: Intermittently. Which side does not have a process to read data written to a pipe and why?

Regards, Joe

Re: ftp/server problem

Steven E. Protter — Mon, 24 Dec 2007 17:40:14 GMT

Shalom,

FTP server security specifically prevents the running of commands.

To properly guage throughput you must upload/download actual files, not try and create them on the fly.

SEP

Re: ftp/server problem

joseph wholey — Mon, 24 Dec 2007 18:09:58 GMT

Shalom to you Steven. That is not an accurate statement you've made. I get this same message when I attempt file transfers as well. And as stated in the original post, this does work intermittently.

Regards, Joe

Re: ftp/server problem

skt_skt — Mon, 24 Dec 2007 18:57:46 GMT

check if you are affecting with any time out settings.. That error sounds like the source/read side process no more exists.

ftp server time out is 15 min while at the client side it is 2 hours(all values defualt; man ftpd)

Re: ftp/server problem

joseph wholey — Wed, 26 Dec 2007 13:35:01 GMT

The strange part is, that the transfer never starts. The message appears immediately.

Re: ftp/server problem

Nicholas Noor_1 — Wed, 26 Dec 2007 23:09:26 GMT

You haven't specified where the disk dump needs to start from and also that you have no mentioned the data content as you have mentioned zero and null in both cases, to void these, you have to have values of data. If you have data and still have problems with dd, then you may be missing parameters with put and it can only hold throughput based on the protocol you use and block size as well depends on it.

There are still more parameters that need to be added and eliminated.. this is one of them.

But make sure you have permissions as well.

Re: ftp/server problem

skt_skt — Wed, 26 Dec 2007 23:18:25 GMT

Let me ask very basic question... How is the ftp process response if you attempt a normal/manual one between these servers?

Re: ftp/server problem

joseph wholey — Thu, 27 Dec 2007 14:02:09 GMT

The network performance is not that good.. 26MB/sec over a gigabit pipe. The reason I use the above command is to rule out "disk lag".
Again, let me reiterate, ftp works intermittently between these two servers. Actually, it works more often than not. I'm trying to pin-point what could be going on (either source or destination) that is generating that error.