[mpich-discuss] mpdboot error: failed to handshake with mpd on 192.168.1.248; recvd output={}

[Zengming Zhang]

Hi all:

Happy New Year!

I am a truly new guy to mpich2 software, and I have a question which
almost put me crazy when installing mpich2 1.2.1, just see the following
contents:

QUESTION:
-----------------------------------------------------------------------
I have installed mpich2 software from source code with the version of
1.2.1 on my Ubuntu 8.10 desktop system. I got no error in building and
installing process, but when I use mpdboot command to start two nodes
which configured in mpd.hosts file, I got the error like this: 

zzm at zzm-desktop:~$ mpdboot -n 2 -f mpd.hosts 
mpdboot_zzm-desktop (handle_mpd_output 407): failed to handshake with
mpd on 192.168.1.248; recvd output={}

There is a more detailed command output here: 
zzm at zzm-desktop:~$ mpdboot -n 2 -f mpd.hosts --chkup -v -d
debug: starting
checking 192.168.1.248
there are 2 hosts up (counting local)
running mpdallexit on zzm-desktop
LAUNCHED mpd on zzm-desktop  via  
debug: launch cmd= /home/zzm/bin/mpich2/bin/mpd.py   --ncpus=1 -e -d
debug: mpd on zzm-desktop  on port 43220
RUNNING: mpd on zzm-desktop
debug: info for running mpd: {'ncpus': 1, 'list_port': 43220,
'entry_port': '', 'host': 'zzm-desktop', 'entry_host': '', 'ifhn': ''}
LAUNCHED mpd on 192.168.1.248  via  zzm-desktop
debug: launch cmd= ssh -x -n -q 192.168.1.248
'/home/zzm/bin/mpich2/bin/mpd.py  -h zzm-desktop -p 43220  --ncpus=1 -e
-d' 
debug: mpd on 192.168.1.248  on port 49130
mpdboot_zzm-desktop (handle_mpd_output 407): failed to handshake with
mpd on 192.168.1.248; recvd output={}

Note that：there are 2 hosts up (counting local)
I think this means that both the two computers could be access, am I
right?
-----------------------------------------------------------------------

COMPUTER CONFIGURATIONS:
-----------------------------------------------------------------------
Some configurations of my computer are listed bellow:
zzm at zzm-desktop:~$ whoami
zzm
zzm at zzm-desktop:~$ more /home/zzm/.mpd.conf 
secretword=nicegiving
zzm at zzm-desktop:~$ chmod 600 .mpd.conf
zzm at zzm-desktop:~$ more /home/zzm/mpd.hosts 
192.168.1.248
192.168.1.190
zzm at zzm-desktop:~$ python -V
Python 2.5.2
zzm at zzm-desktop:~$ 

The IP address of the main computer is 192.168.1.190, domain name is:
zzm-desktop, and all commands are run on it. 
192.168.1.248 is another computer used to test parallel environment,
which domain name is : zcni-desktop. 

The /etc/hosts files on each computers are:
zzm at zzm-desktop:~$ more /etc/hosts
192.168.1.190   zzm-desktop
... ...
1zzm at zcni-desktop:~$ more /etc/hosts
192.168.1.190   zcni-desktop
... ...

Another thing, I do can access zcni-desktop via SSH protocol without
entering a password. The only thing is that I must wait a long time, for
example 10 seconds, to get login to zcni-desktop.
So, in order to avoid SSH timed out, I add "UseDNS no" at the
of /etc/ssh/sshd_config on each of the two computers.
So, I can access to zcni-desktop via SSH immediately.

The mpich2 installation folder are already on each of computer, and the
$MPICH2/bin has been added into $PATH as well on each computer:
zzm at zzm-desktop:~/bin/mpich2$ ls
bin  etc  include  lib  sbin  share
zzm at zzm-desktop:~/bin/mpich2$ pwd
/home/zzm/bin/mpich2
zzm at zzm-desktop:~/bin/mpich2$ which mpd
/home/zzm/bin/mpich2/bin/mpd

zzm at zcni-desktop:/home/zzm/bin/mpich2$ ls
bin  etc  include  lib sbin  share
zzm at zcni-desktop:/home/zzm/bin/mpich2$ pwd
/home/zzm/bin/mpich2
zzm at zcni-desktop:/home/zzm/bin$ which mpd
/home/zzm/bin/mpich2/bin/mpd
-----------------------------------------------------------------------

WHAT DID I DO TO FIX IT:
-----------------------------------------------------------------------
And I do can run these commands on each individual computer:
zzm at zzm-desktop:~$ mpd &
[1] 9219
zzm at zzm-desktop:~$ mpdtrace
zzm-desktop
zzm at zzm-desktop:~$ mpdallexit
[1]+  Done                    mpd
zzm at zzm-desktop:~$ 
zzm at zcni-desktop:~$ mpd &
[1] 9219
zzm at zcni-desktop:~$ mpdtrace
zcni-desktop
zzm at zcni-desktop:~$ mpdallexit
[1]+  Done                    mpd
zzm at zcni-desktop:~$


I also used mpdcheck command on each computer, and got an error report
when using -ssh option: 

zzm at zcni-desktop:~$mpdcheck
zzm at zcni-desktop:~$

zzm at zzm-desktop:~$ mpdcheck
zzm at zzm-desktop:~$ mpdcheck -f mpd.hosts 
zzm at zzm-desktop:~$ 

zzm at zzm-desktop:~$ mpdcheck -f mpd.hosts -ssh
** timed out waiting for client on 192.168.1.248 to produce output
client on 192.168.1.248 failed to access the server
here is the output:
zzm at zzm-desktop:~$


But I do can access 192.168.1.248 via SSH and without entering a
password as I mentioned above(in "COMPUTER CONFIGURATIONS:" part ).

I also thought about that whether the port is open, is the firewall that
cause the problem? But I run the following command on both computer and
still got the error:
zzm at zzm-desktop:~/bin/mpich2/bin$ sudo iptables -F
[sudo] password for zzm: 
zzm at zzm-desktop:~/bin/mpich2/bin$ 

zzm at zcni-desktop:/home/zzm/bin/mpich2/bin$ sudo iptables -F
[sudo] password for zzm:
zzm at zcni-desktop:/home/zzm/bin/mpich2/bin$

So, as I have mentioned, anyone could give me a clue? Please help me get
out of the problem, any words of you would be appreciated very much!

Thanks in advance!

Best regards,
Zengming
ZheJiang Univ. HangZhou, China