UCS dynamic vnic-policy

Unanswered Question
Jul 24th, 2012
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the Palo Adapter (M81KR) supports only 54 dynamic vnics per server-profile.

Stupid question: Does this mean, in a vm-fex (formerly vn-link in hardware) environment, i can assign maximum 54 VMs per ESXi Host?

Currently we have the problem, that a vMotioned VM loses network-connectivity. We have powered-down another VM and vMotioned again the VM, this time network connectivity wasn`t lost.

Any ideas?

KR Gregor

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We are using the M81KR and vm-fex with a 52 dynamic nics. Console and vmotion we run on a standard vswitch using 2 nics. That does mean we can run only 52 VM's but have had no issues with vmotion.

UCS 1.4(1m) to start and upgraded to 2.0(1t) now, ESXi 4.1.

We're just starting to test the same setup with the M3 blades and the VIC 1240, which should get 116 PCI devices on that card.

gstoek Wed, 07/25/2012 - 00:35
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forgot to mention: ucs version 2.0.3a , ESXi 5.0 Build 721882

Robert Burns Wed, 07/25/2012 - 06:32
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Keep in mind the max # of vnics is dependent on a few things.

-Adapter Limitations

-UCSM Limitations

-Network Limitation (IOM type and acknowledged uplinks)

-Host OS Limitations

The first limiation you'll likely hit is the 112 Dynamic vNICs with ESX 5.  For ESX 4.0/4.1U1 the limit was 54.


If you're expecting to hit the 116 dynamic vnic limit you'll need a 2208 IOM.  First generation IOM will only yield 54 max Dynamic vNICs.



gstoek Wed, 07/25/2012 - 10:36
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Hi Robert,

we have IOM 2104 with four uplinks...so we should be able to use the maximum # of 54.

We have about 30-35 VMs running, each with only one NIC, so we shouldn`t hit this limitation.

We have a case opened with VMware but Cisco will be involved now.

KR Gregor

Marcelo Almeida... Tue, 11/10/2015 - 17:54
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Hi All,

although it's an old post, I would like to add some references for others with the same doubt:

Check the Configuration Limits link (UCS 6100 and 6200 Configuration Limits for UCSM) for a specific release.

Hope this helps.


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