PBS on multihomed VMs


#1

Hi folks,

Could someone help me build a PBS complex on VMs that have multiple network interfaces?

I built several virtual machines running CentOS 7.4 with Vagrant and VirtualBox so that they can communicate each other via VirtualBox’s “internal” network (192.168.0.*).
In addition, VirtualBox automatically creates a mandatory “host-only” network (10.0.2.15) on each VM as eth0, which connects the host (physical) machine and the VM.
The host-only network cannot be used for VM-to-VM communication.
I thought PBS communicates via the internal network (192.168.0.*).

[node00]
eth0: 10.0.2.15 = host-only network
eth1: ***.***.2.90 = bridged network (global IP not shown)
eth2: 192.168.0.100 = internal network

[node01]
eth0: 10.0.2.15 = host-only network
eth1: 192.168.0.101 = internal network

I installed PBS Pro 17.1.0 on these two VMs and started it.

node00:~$ sudo service pbs status
pbs_server is pid 23916
pbs_mom is pid 23598
pbs_sched is pid 23613
pbs_comm is 23568

node01:~$ sudo service pbs status
pbs_mom is pid 20422

Then I’ve got the following logs in server_logs.

01/15/2018 16:23:06;0001;Server@node00;Svr;Server@node00;is_request, bad attempt to connect from 10.0.2.15:15003

I guess the MoM on node01 reports her IP as 10.0.2.15, which confuses the server on node00 since the same IP exists on node00.
I’ve read ‘PBS with Multihomed Systems’ (IG-62) and ‘Name Resolution and Network Configuration’ (IG-8), but they are kind of too abstract for me. X-(
For now I’ve confirmed that ‘hostname -i’ returns the internal network address (192.168.0.*).

node01:~$ hostname -i
192.168.0.101

What can I do in this situation?
Any comments or suggestions would be appreciated. Thank you,


#2

If you want the mom to report a specific IP (out of a list of IPs) please add the following to the /etc/pbs.conf file of your mom.
PBS_LEAF_NAME=192.168.0.10x

There seems to be a bug in the latest master of PBS Pro that has a problem with the order of IP’s used. For example, in this case it is not using the IP listed by hostname -i.

Thanks and Regards,
Subhasis


#3

Hi subhasisb

Thank you for your concern.
Now with PBS_LEAF_NAME they work fine. :slight_smile:
I’ll be happy if PBS folks find this report useful.

Regards,