Re: [OMPI users] How do you change ports used?

[Vincent via users]

On 09/03/2021 11:23, Sendu Bala via users wrote:

When using mpirun, how do you pick which ports are used?

I???ve tried:

mpirun --mca btl_tcp_port_min_v4 46207  --mca btl_tcp_port_range_v4 32 --mca 
oob_tcp_keepalive_time 45 --mca oob_tcp_max_recon_attempts 20 --mca 
oob_tcp_retry_delay  1 --mca oob_tcp_keepalive_probes 20 --mca 
oob_tcp_keepalive_intvl 10 true

And also setting similar things in openmpi/etc/openmpi-mca-params.conf :
btl_tcp_port_min_v4 = 46207
btl_tcp_port_range_v4 = 32
oob_tcp_keepalive_time = 45
oob_tcp_max_recon_attempts = 20
oob_tcp_retry_delay = 1
oob_tcp_keepalive_probes = 20
oob_tcp_keepalive_intvl = 10

But when the process is running:

ss -l -p -n | grep "pid=57642,"
tcp  LISTEN 0  128127.0.0.1:58439 
0.0.0.0:*   users:(("mpirun",pid=57642,fd=14))
tcp  LISTEN 0  128  0.0.0.0:36253 
0.0.0.0:*   users:(("mpirun",pid=57642,fd=17))

What am I doing wrong, and how do I get it to use my desired ports (and other 
settings above)?



Hello

Could this be related to some recently resolved bug ?
What version are you running ?
Having a look on https://github.com/open-mpi/ompi/issues/8304 could be 
possibly useful?


Regards

Vincent.

Re: [OMPI users] [ORTE] Connecting back to parent - Forcing tcp port

[Vincent via users]

On 07/01/2021 19:51, Josh Hursey via users wrote:
I posted a fix for the static ports issue (currently on the v4.1.x 
branch):

https://github.com/open-mpi/ompi/pull/8339

If you have time do you want to give it a try and confirm that it 
fixes your issue?



Hello Josh

Definitely yes ! It does not crash anymore and I see through ss/netstat 
the orted process is connecting to the port I specified. Good work. 
Thank you.


I wish you a happy 2021.

Regards

Vincent.




Thanks,
Josh


On Tue, Dec 22, 2020 at 2:44 AM Vincent > wrote:


On 18/12/2020 23:04, Josh Hursey wrote:

Vincent,

Thanks for the details on the bug. Indeed this is a case that
seems to have been a problem for a little while now when you
use static ports with ORTE (-mca oob_tcp_static_ipv4_ports
option). It must have crept in when we refactored the internal
regular expression mechanism for the v4 branches (and now that I
look maybe as far back as v3.1). I just hit this same issue in
the past day or so working with a different user.

Though I do not have a suggestion for a workaround at this time
(sorry) I did file a GitHub Issue and am looking at this issue.
With the holiday I don't know when I will have a fix, but you can
watch the ticket for updates.
https://github.com/open-mpi/ompi/issues/8304

In the meantime, you could try the v3.0 series release (which
predates this change) or the current Open MPI master branch
(which approaches this a little differently). The same command
line should work in both. Both can be downloaded from the links
below:
https://www.open-mpi.org/software/ompi/v3.0/
https://www.open-mpi.org/nightly/master/

Hello Josh

Thank you for considering the problem. I will certainly keep
watching the ticket. However, there is nothing really urgent (to
me anyway).



Regarding your command line, it looks pretty good:
  orterun --launch-agent /home/boubliki/openmpi/bin/orted -mca
btl tcp --mca btl_tcp_port_min_v4 6706 --mca
btl_tcp_port_range_v4 10 --mca oob_tcp_static_ipv4_ports 6705
-host node2:1 -np 1 /path/to/some/program arg1 .. argn

I would suggest, while you are debugging this, that you use a
program like /bin/hostname instead of a real MPI program. If
/bin/hostname launches properly then move on to an MPI program.
That will assure you that the runtime wired up correctly
(oob/tcp), and then we can focus on the MPI side of the
communication (btl/tcp). You will want to change "-mca btl tcp"
to at least "-mca btl tcp,self" (or better "-mca btl
tcp,vader,self" if you want shared memory). 'self' is the
loopback interface in Open MPI.

Yes. This is actually what I did. I just wanted to be generic and
report the problem without too much flourish.
But it is important you reminded this for new users, helping them
to understand the real purpose of each layer in an MPI implementation.



Is there a reason that you are specifying the --launch-agent to
the orted? Is it installed in a different path on the remote
nodes? If Open MPI is installed in the same location on all nodes
then you shouldn't need that.

I recompiled the sources, activating
--enable-orterun-prefix-by-default when running ./configure. Of
course, it helps :)

Again, thank you.

Kind regards

Vincent.




Thanks,
Josh




--
Josh Hursey
IBM Spectrum MPI Developer

Re: [OMPI users] [ORTE] Connecting back to parent - Forcing tcp port

[Vincent via users]

On 18/12/2020 23:04, Josh Hursey wrote:

Vincent,

Thanks for the details on the bug. Indeed this is a case that seems to 
have been a problem for a little while now when you use static ports 
with ORTE (-mca oob_tcp_static_ipv4_ports option). It must have crept 
in when we refactored the internal regular expression mechanism for 
the v4 branches (and now that I look maybe as far back as v3.1). I 
just hit this same issue in the past day or so working with a 
different user.


Though I do not have a suggestion for a workaround at this time 
(sorry) I did file a GitHub Issue and am looking at this issue. With 
the holiday I don't know when I will have a fix, but you can watch the 
ticket for updates.

https://github.com/open-mpi/ompi/issues/8304

In the meantime, you could try the v3.0 series release (which predates 
this change) or the current Open MPI master branch (which approaches 
this a little differently). The same command line should work in both. 
Both can be downloaded from the links below:

https://www.open-mpi.org/software/ompi/v3.0/
https://www.open-mpi.org/nightly/master/

Hello Josh

Thank you for considering the problem. I will certainly keep watching 
the ticket. However, there is nothing really urgent (to me anyway).



Regarding your command line, it looks pretty good:
  orterun --launch-agent /home/boubliki/openmpi/bin/orted -mca btl tcp 
--mca btl_tcp_port_min_v4 6706 --mca btl_tcp_port_range_v4 10 --mca 
oob_tcp_static_ipv4_ports 6705 -host node2:1 -np 1 
/path/to/some/program arg1 .. argn


I would suggest, while you are debugging this, that you use a program 
like /bin/hostname instead of a real MPI program. If /bin/hostname 
launches properly then move on to an MPI program. That will assure you 
that the runtime wired up correctly (oob/tcp), and then we can focus 
on the MPI side of the communication (btl/tcp). You will want to 
change "-mca btl tcp" to at least "-mca btl tcp,self" (or better "-mca 
btl tcp,vader,self" if you want shared memory). 'self' is the loopback 
interface in Open MPI.
Yes. This is actually what I did. I just wanted to be generic and report 
the problem without too much flourish.
But it is important you reminded this for new users, helping them to 
understand the real purpose of each layer in an MPI implementation.




Is there a reason that you are specifying the --launch-agent to the 
orted? Is it installed in a different path on the remote nodes? If 
Open MPI is installed in the same location on all nodes then you 
shouldn't need that.
I recompiled the sources, activating --enable-orterun-prefix-by-default 
when running ./configure. Of course, it helps :)


Again, thank you.

Kind regards

Vincent.




Thanks,
Josh