RSH connection problem while running MPI program

I'm trying to run MPI programs on 8 machines, but I get the error

connect to address 127.0.0.1 port 544: Connection refused
Trying krb4 rsh...
connect to address 127.0.0.1 port 544: Connection refused
trying normal rsh (/usr/bin/rsh)
lagrid02: Connection refused

When I run it with a machinefile option, I get the error

lagrid03: No route to host

where lagrid03 is the neighbouring node connected to master node.

How should I rectify this ?

What OS are you trying to run these MPI programs on? paste output from

uname -spr

Using Centos 5
uname -spr gives
Linux 2.6.18-238.12.1.el5xen x86_64

Try this URL and see if it helps you

http://www.open-mpi.org/faq/?category=rsh

Plus, can you try this on the shell:

telnet localhost 544

also post output from

netstat -apn|grep -w 544|grep LISTEN

Post output from

iptables -L
telnet localhost 544
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
telnet: Unable to connect to remote host: Connection refused

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     udp  --  anywhere             anywhere            udp dpt:domain 
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:domain 
ACCEPT     udp  --  anywhere             anywhere            udp dpt:bootps 
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:bootps 
RH-Firewall-1-INPUT  all  --  anywhere             anywhere            

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             192.168.122.0/24    state RELATED,ESTABLISHED 
ACCEPT     all  --  192.168.122.0/24     anywhere            
ACCEPT     all  --  anywhere             anywhere            
REJECT     all  --  anywhere             anywhere            reject-with icmp-port-unreachable 
REJECT     all  --  anywhere             anywhere            reject-with icmp-port-unreachable 
RH-Firewall-1-INPUT  all  --  anywhere             anywhere            

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Chain RH-Firewall-1-INPUT (2 references)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     icmp --  anywhere             anywhere            icmp any 
ACCEPT     esp  --  anywhere             anywhere            
ACCEPT     ah   --  anywhere             anywhere            
ACCEPT     udp  --  anywhere             224.0.0.251         udp dpt:mdns 
ACCEPT     udp  --  anywhere             anywhere            udp dpt:ipp 
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:ipp 
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED 
ACCEPT     tcp  --  anywhere             anywhere            state NEW tcp dpt:ssh 
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited 

Do you need iptables? if not just disabling it will be the simplest solution.

chkconfig disable iptables

And

service iptables stop

Try telnet to port 544 after disabling iptables.

I used iptables because I had to connect the machine in the internal network to the internet through a gateway.
Is there any round about method which might not require me to disable iptables ?

Disable it temporarily. Turn the service off. Test if it works. If it works we can add a rule and start it back up.

Plus, I think you did not paste the output from

netstat -apn|grep -w 544|grep LISTEN.

It could be that you don't have any process listening on port 544, which seems like the cause.

netstat -apn|grep -w 544|grep LISTEN
did not give any output.

What should I do about it ?