04-16-2010 07:16 AM - edited 03-06-2019 10:39 AM
I have a dumb (unmanaged 8-port Linksys Gig switch) which we are currently using for some linux clustering servers. It works fine, but I want to move the servers to our 6500. When I moved them from the switch to our 6500, the cluster breaks because multicast isn't working in the same way as it is on the unmanaged switch. Each server has 3 NIC interfaces, (Production network routed, iSCSI private, and metadata (multicast) private) so one physical port is residing on it's own VLAN. All server interfaces are static IP assignments. The other 2 VLANs are working properly, the metadata VLAN seemingly is breaking the cluster because they can't communicate via multicast. Vlan 999 is for the clustering metadata, and is defined as a VLAN.
I had defined vlan 999 as a SVI with no ip address and enabling pim sparse-dense-mode, but that didn't work for the servers either.
I would appreciate any help in getting the member ports of that vlan to act like the dumb switch the servers are now on. The multicast traffic needs to stay isolated (like it is on the separate switch). All the vlan ports are on the same line card.
Global Config:
ip multicast-routing
Vlan config:
vlan 999
name Data_iSCSI_Metadata
!
port config:
interface GigabitEthernet4/33
switchport
switchport access vlan 999
spanning-tree portfast
!
Solved! Go to Solution.
04-16-2010 09:42 AM
Okay, looks like the command is not available on your switch. Apologies for that.
You are correct, with a 6500 running SXH you should turn off IGMP snooping under the vlan interface. So you could do one of 2 things -
create a L3 vlan interface for 999 and then
1) turn off IGMP snooping under the interface in which case the multicast traffic should be flooded to all ports in that vlan
or
2) configure the IGMP snooping querier function for that vlan so that only the ports that want the multicast traffic get it
Jon
04-16-2010 07:42 AM
dklusmann wrote:
I had defined vlan 999 as a SVI with no ip address and enabling pim sparse-dense-mode, but that didn't work for the servers either.
I would appreciate any help in getting the member ports of that vlan to act like the dumb switch the servers are now on. The multicast traffic needs to stay isolated (like it is on the separate switch). All the vlan ports are on the same line card.
Global Config:
ip multicast-routing
Vlan config:
vlan 999
name Data_iSCSI_Metadata
!
port config:
interface GigabitEthernet4/33
switchport
switchport access vlan 999
spanning-tree portfast
!
try adding this in your config -
no igmp snooping vlan 999
Jon
04-16-2010 08:18 AM
Thank you. Isn't that command only available for a SVI? (no ip igmp snooping)
I don't mind defining an interface vlan for use of the command, but want to make sure I actually need to do so.
Does multicast not work in a plain old vlan, but does work in an interface vlan?
04-16-2010 08:57 AM
dklusmann wrote:
Thank you. Isn't that command only available for a SVI? (no ip igmp snooping)
I don't mind defining an interface vlan for use of the command, but want to make sure I actually need to do so.
Does multicast not work in a plain old vlan, but does work in an interface vlan?
The command is available for the vlan ie. you simply use the vlan id you don't want IGMP snooping on -
http://www.cisco.com/en/US/docs/ios/ipmulti/command/reference/imc_02.html#wp1046498
I thought you wanted to make the vlan act as a dumb switch ie. in effect turn off multicast for vlan 999 ?
Jon
04-16-2010 09:21 AM
I don't think I want to turn off multicast, I guess it is needed for the cluster members to talk to each other.
But that's what I don't understand regarding our current setup. Everything is working using a dedicated Linksys/Cisco SD2008 (unmanaged switch) for those 3 servers, and the cluster is functional/working, etc. but is hardly scalable for a virtualization environment.
I want the ports/vlan on the switch to be essentially configured the same as the dumb switch, since it's working as expected in that configuration it should be easy to configure it on the 6509.
WS-C6509-E running 12.2(33)SXH
When I enter the command on the switch for the ports (not the vlan) it drops me out of the interface to the config prompt.
Core_6509E(config)#int gi4/33
Core_6509E(config-if)#no ip igmp snooping vlan 999
^
% Invalid input detected at '^' marker.
Core_6509E(config-if)#no ip igmp snooping
Core_6509E(config)#
Core_6509E(config)#vlan 999
Core_6509E(config-vlan)#no ip igmp snooping vlan 999
^
% Invalid input detected at '^' marker.
Core_6509E(config-vlan)#exit
Core_6509E(config)#no ip igmp snooping vlan 999
^
% Invalid input detected at '^' marker.
Core_6509E(config)#exit
Core_6509E#no ip igmp snooping vlan 999
^
% Invalid input detected at '^' marker.
Core_6509E#
Is this expected?
04-16-2010 09:42 AM
Hello DKlusman,
the command has to be given under the SVI L3 interface
interface vlan 999
no ip igmp snooping
see
you should consider the use of IGMP snooping querier instead that allows to use IGMP snooping forwarding optimization features
but the SVI will need an ip address to be used as source for the IGMP queries
Router# interface vlan 200
Router(config-if)# ip address 172.20.52.106 255.255.255.248
Router(config-if)# igmp snooping querier
Router(config-if)# end
http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SXF/native/configuration/guide/snooigmp.html#wp1050624
Hope to help
Giuseppe
04-16-2010 09:42 AM
Okay, looks like the command is not available on your switch. Apologies for that.
You are correct, with a 6500 running SXH you should turn off IGMP snooping under the vlan interface. So you could do one of 2 things -
create a L3 vlan interface for 999 and then
1) turn off IGMP snooping under the interface in which case the multicast traffic should be flooded to all ports in that vlan
or
2) configure the IGMP snooping querier function for that vlan so that only the ports that want the multicast traffic get it
Jon
04-16-2010 04:15 PM
Thank you.
Turning IGMP snooping off was the key.
Interface Vlan 999
no ip address
ip pim sparse-dense-mode
no ip igmp snooping
end
This works.
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