ftp Session Hangs with Large Transfer

[sunil_21]

CU is having the HPUX Server in DMZ under Checkpoint firewall ? While Doing ftp From PC to HPUX the FTP Session Hangs with HPUX 11i?
Anybody having Solution on this ?

Thanks in advancd

[Brian Crabtree]

Hmm. You might want to check the timeout settings in your firewall, and see if the connection is passing a certin time threshold (ie: 30 minutes).

Otherwise, you could have them set hash marks on (painful, yes), and see if it is stopping or halting at a specific point. They would probably want to script an FTP transfer doing this though, as the hash-marks will be alot (1 per 1k transfered, someone else might know how to increase this).

Just a thought.

Thanks,

Brian

[Stefan Farrelly]

Something is timing out you ftp session. Unlikely its on the HP - look at your firewall/network team.

I believe we used to get around this by running a ping to the remote ftp site while the ftp was running (from a different shell/window), this kept the session 'alive' and stopped it timing out. Give it a try (as long as your firewall doesnt block ping!).

[sunil_21]

Hi

Thanks to you for reply
In the same DMZ they are using the IBM RS6000 Its FTP seesion Working fine And Customer Asking why the HP-UX server having the problem we had made the Necessary chages at firewall side

[Steven E. Protter]

It is possible that the Checkpoint firewall(which we used to use) has not been properly patched. That needs to be checked because we've fixed these symptoms by patching the firewall.

Further if the HP-UX system does not have largefiles enabled on the target filesystem and the file is being uploaded to the HP-UX server, the transfer will stop at exactly 2 Gigabytes.

To enable largefiles:

umount the filesystem if possible.

Use the fsadm command to convert the filesystem. Do not change /etc/fstab largefiles directive is no longer supported in there.

If you can umount, you could also rebuild the fs as follows:

newfs -F vxfs -o largefiles /dev/vg00/rlvol##

#adjust the /dev statement to reality

mount the filesystem and you're done.

check dmesg

inetd -l for enhanced logging:

tail -f /var/adm/syslog/syslog.log to watch this problem develop as it happens.

SEP

[sunil_21]

Hello

FTP session is not hangs after 2GB transfer
Its Stop In between after 50 MB also,
All ARPA patches and Btlan Driver Updated on HP-UX side, Within DMZ Ftp Working fine
Its Not working within LAN ?

Sunil

[Suresh Patoria]

Hi,

create the /var/adm/syslog/xferlog file

then enable ftp logging in /etc/inetd.conf usining -t option

and also check the /etc/ftpd/ftpaccess file

there is any restriction

thanx

[Stefan Farrelly]

In my opinion these problems are almost always network related - usually with your network switch/hub/router/firewall. And almost always your network people say it is nothing to do with them. Finding good network admins is very hard:-)

Things to check;
1. autonegotation. Is your lan card set to same speed on HP-UX as the hub/switch it plugs into, ie. both set to 100MB FD, or Auto ? If not this causes a speed mismatch which can cause ftp to hang/die.
2. Get your network guys to check their network equipment again, eg. patches/firmware - as pointed out in earlier replies. They will be reluctant to do this but youve got to keep at them as you need their help to fix it.
3. Try something different. Plug your HP into a different hub/switch, or different lan card if possible to try to isolate where the problem is.