Question

NLB Unicast mode also tries to communicate in multicast mode

Asked by: DanniBachPedersen

Hey Guys´N´Girls

I have an NLB cluster running in UNICAST mode that contains 8 servers. (it is not an option to run multicast.)
BUT..... I can see that is also tries to "talk" to the servers through MULTICAST mode???
ummm WHY??
how can that be possible?
I really hope someone can help me out here?

/D

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Asked On
2009-11-06 at 02:06:07ID24877399
Tags

Network Load Balancing

Topics

Windows Networking

,

Microsoft Operating Systems

,

MS Forefront-ISA

Participating Experts
1
Points
500
Comments
13

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Answers

 

by: keith_alabasterPosted on 2009-11-07 at 00:58:08ID: 25765502

Please read the help section http://www.experts-exchange.com/help.jsp?hs=26

Is this a SUN cluster?
Is this on HP c-Class Blades?
Is your middle name Bob?
Are you using the iPhone multi-user operating system?

Bottom line, you have told us absolutely nothing about the environment, operating system, setup or the configuration itself so we can only guess at what the issue might be. If you can advise on the full scenario, it will make it much simpler for someone to try and assess the position and give you some meaningful suggestions.

Keith

 

by: DanniBachPedersenPosted on 2009-11-08 at 23:20:32ID: 25773907

Hey Keith

The reasson for that is that i can. im simply not allowed to tell anything about our infrastructure. i know it can be a bit hard to help med with so little info. but ille try to answer your questions.

1, microsoft NLB cluster
2. Yes.. it is C-class HP blade
3. My middle name is Bach, and not Bob
4. I have sold my Iphone - And bought a HTC Hero

/D

 

by: keith_alabasterPosted on 2009-11-08 at 23:23:51ID: 25773925

lol :)

Without knowing the environment, as i am sure you appreciate, this really is pretty much impossible to move forward with.

Are you able to attach the output of the cluster.log files?

 

by: DanniBachPedersenPosted on 2009-11-09 at 00:23:00ID: 25774143

Hey Keith

Thx for the quick responce..

i can no show any logfiles but i can type here what we can see through our surveillance.

<188>91373: HVI-B855-ts_S150: Nov 4 11:45:05.520: %SW_DAI-4-DHCP_SNOOPING:1 Invalid ARP´s (res) on G1/0/2, vlan 7
([MULTICAST Mac adress/IP adress/UNICAST Mac adress/IPadress/time CET Fri Nov 6 2009 ])

hope this helps.

/D

 

by: DanniBachPedersenPosted on 2009-11-09 at 00:24:23ID: 25774144

ERROR

DHCP_SNOOPING_DENY   DENY is missing in the tekst before

/D

 

by: keith_alabasterPosted on 2009-11-09 at 02:06:15ID: 25774600

Can each of the individual IP addresses be pinged successfully that comprise the cluster? An arp failure associated with a particular vlan suggests that one or more systems cannot see that vlan or that members of the cluster are not necessarily in the same vlan.

 

by: DanniBachPedersenPosted on 2009-11-09 at 02:30:10ID: 25774694

All servers can be pinged. but we have security that denies ping. but with that off, they can all be pinged.

 

by: keith_alabasterPosted on 2009-11-09 at 02:54:50ID: 25774790

Is this actually causing you a problem or is it just a query?
Checking my own clusters - although these are all two node active/passive clusters - I can see that intermittently I am also seeing a couple of multicasts. These are not impacting my systems in any way though.

 

by: DanniBachPedersenPosted on 2009-11-09 at 03:31:51ID: 25774929

Hey.

these are not causing me any problems (besides a big logfile). But i didnt know what it was so had to see if i could find anyone the knew anything about it.

on my system these shows up several times an hour. 10o 30 min between every logentry

 

by: keith_alabasterPosted on 2009-11-09 at 03:53:27ID: 25775036

Mine is less than that - I get about one or two an hour but then, I have six less servers in the cluster than you do :)

To be frank, I would suggest you simply ignore them.

 

by: DanniBachPedersenPosted on 2009-11-09 at 05:08:14ID: 25775545

ok... i thing that is what ill suggest then. thx for the help.
/D

 

by: keith_alabasterPosted on 2009-11-09 at 05:25:51ID: 25775656

Welcome. If we need to do more here then just comment on the bottom of this qustionand I'll pick it up.

Keith

 

by: DanniBachPedersenPosted on 2009-11-09 at 06:04:38ID: 25775973

Thx Keith

great :)

20120131-EE-VQP-002

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