how can we reduce multicast traffic ?

[bread-baker]

note the multicast traffic from out Layer 3 switch:

ifIndex    417
Octets Received    6673610456
Packets Received Without Errors    24005319
Unicast Packets Received    1431638
Multicast Packets Received    16965403
Broadcast Packets Received    5608278
Receive Packets Discarded    5125808
Octets Transmitted    5415839494
Packets Transmitted Without Errors    14709701
Unicast Packets Transmitted    1116418
Multicast Packets Transmitted    13127913
Broadcast Packets Transmitted    465370
Transmit Packets Discarded    0
Most Address Entries Ever Used    241
Address Entries in Use    198
Maximum VLAN Entries    1024
Most VLAN Entries Ever Used    10
Static VLAN Entries    9
Dynamic VLAN Entries    0
VLAN Deletes    4
Time Since Counters Last Cleared    12 day 21 hr 50 min 6 sec

We have a 2-node drbd cluster and a few pve-desktops for backup.

We'd like to cut down the network traffic.

The 2 cluster hosts have a a dedicated connection for drbd. Could we use that for cluster multicasts? If so is it the hostname's IP address used to send multicast?

Or is multicast sent out on all interfaces? [ these systems have 4 nics ].


For pve desktops which are not yet part of a cluster , is there a way to turn off the multicast traffic?

 

[e100]

The interface used is based on the IP associated with hostname in /etc/hosts

I have mine running on a bond interface that is made up of redundant Infiniband connections.
We are up to 19 nodes on that setup now, 16 of them also running DRBD traffic on the same bonded Infiniband ports.

Maybe an iptables rule preventing the multicast would be a simple way to turn off the multicast traffic.

 

[RobFantini]

The interface used is based on the IP associated with hostname in /etc/hosts

thanks i was easily able to change the cluster to use a nic to nic patch cable after following that.

I have mine running on a bond interface that is made up of redundant Infiniband connections.
We are up to 19 nodes on that setup now, 16 of them also running DRBD traffic on the same bonded Infiniband ports.

what brand/model card do you generally get ?

Maybe an iptables rule preventing the multicast would be a simple way to turn off the multicast traffic.

I'll do that on non cluster pve systems.

Also:
We are setting up a bunch of pve-desktops to be use in the future with ceph , sheepdog or which ever network cluster system makes sense a year from now.
Does anyone know if multicast is used on ceph ? If so i will not bother disabling .