FTP issue

[joe_91]

Hi There:

Two Kclass boxes. Fddi cards. 11.0. 64 bit. ftp takes forever. No name resolution problem. dns entry first in resolv.conf and nsswitch.conf. both servers in same subnet. Please advice.

Thanks
Joe.

[Shannon Petry]

First to prove whether or not it's a name resolution problem you need to ftp to the address and not say that your resolve.conf and nsswitch.conf are fine.
ftp joe.ws.net
ftp 10.11.12.13
is thru-put the same?
Next, is it only one server which is slow and the other normal speed?
I.E.
ftp from server 1 to server 2
get bigfile
ftp from server 2 to server 1
get bigfile

if they are both slow, then you have networking issues.

[Rich Wright]

I'm thinking that you have a bad fddi card. Here is a script that we use to check for fibre errors. You can probably modify it for fddi.
#!/bin/sh
for file in $(ioscan -kfnd fcT1_cntl | grep .dev.fcms | sed 's/ //g')
do
echo $file
fcmsutil $file stat
done
for file in $(ioscan -kfnd td | grep .dev.td | sed 's/ //g')
do
echo $file
fcmsutil $file stat
done

With fddi, the side showing the errors is usually good and the next server over is the bad one.

I hope this makes sense.

[joe_91]

Hi:
Thanks. Should i add FDDI after the ioscan command in the script, please help me with that.

Thanks
Joe.

[rick jones]

i thought that fcmsutil was for fibre channel cards, not FDDI cards?

there are HP-PB and HSC FDDI cards - which are in your K's?

can you reproduce the slot data rate with netperf (http://www.netperf.org) instead of FTP?

what does netstat -p tcp look like before and after a transfer - better still, run the before and after through "beforeafter" from ftp.cup.hp.com and just show the deltas

if retransmissions are being show, what do the lanadmin stats (lanadmin -g mibstats ) look like for before/after the transfer

[Tom Danzig]

I may be talking out my a** as i am not familiar with FDDI, however, most slow transfer problem I have seen from two hosts on the same subnet (using TCP/IP) are improper duplex settings on one of the hosts. I don't know if FDDI uses half/full duplexing though.

[rick jones]

FDDI doesn't really do full-duplex sorts of things - it is composed of dual counter-rotating rings. one ring is the primary ring - data comes-in on one side and goes back out the other, some is siphoned off to or put-on by the host. if there is a break somewhere the nodes on iether side of the break wrap the primary onto the secondary to keep a working ring going.

Now, if you had switched FDDI versus concentrators (hub-like devices for FDDI) and had the right sort of FDDI chips (DEC I think) and right sort of switch (DEC GigaSwitch IIRC), then if a single station were connected to the switch, it could indeed get connected in a full-duplex manner. I'm pretty sure that sort of stuff was rather more robust than the autoneg in 100BT appears to be.