• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 303
  • Last Modified:

Dell PowerConnect Static LAG Hashing with ESXi 5.5

In setting up a static LAG between a Dell PowerConnect Switch and ESXi, on the ESXi vswitch configuration side it is recommended to use "Route Based on IP hash". This will be how VMware will handle the distribution of the load.

Here's one VMware article on this: https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1004048

In the network world, does the Dell switch have to have the same Hash algorithm as VMware? Below are the 7 LAG hash algorithm the Dell switch comes with.  By default all LAGs are setup with "Enhanced hashing mode". Nothing in the above VMWARE article states that you have to set the switch Hashing algorithm. And to me it seems that this wouldn't HAVE to match VMware.

But I'm just double checking with anyone out there that knows for sure what has to be done. Thanks.

Source MAC, VLAN, EtherType, and incoming port.
• Destination MAC, VLAN, EtherType, and incoming port.
• Source IP and Source TCP/UDP port numbers.
• Destination IP and Destination TCP/UDP port numbers.
• Source/Destination MAC, VLAN, EtherType, and incoming port.
• Source/Destination IP and Source/Destination TCP/UDP port numbers.
• Enhanced hashing mode
Enhanced hashing mode has following advantages:
• MODULO-N operation based on the number of ports in the LAG.
• Packet attributes selection based on the packet type. For layer-2 packets,
Source and Destination MAC address plus physical source port are used
for hash computation. For IP packets, Source IP, Destination IP address,
TCP/UDP ports, and physical source port are used.
• Non-Unicast traffic and Unicast traffic is hashed using a common hash
algorithm.
982 Link Aggregation
• Excellent load balancing performance.
0
RFVDB
Asked:
RFVDB
  • 2
1 Solution
 
ArneLoviusCommented:
Inbound and outbound traffic in a LAG does not have to match.

The more inputs to the hashing algorithm,  the more opportunity you have for load distribution to work well (consider just two end devices) , but it does not guarantee better load balancing, as some flows will be longer lasting than others (consider a HD video stream compared to FTP copying multiple small files).
0
 
RFVDBAuthor Commented:
Calling Dell Pro Support it turns out that the hashing algorithm does need to change to No: 6 - • Source/Destination IP and Source/Destination TCP/UDP port numbers.

VMware uses "Route based on IP hash" and I guess that plays well with the above.

That fixed the issue.
0
 
RFVDBAuthor Commented:
I figured it out myself by calling Dell Pro Support
0

Featured Post

2018 Annual Membership Survey

Here at Experts Exchange, we strive to give members the best experience. Help us improve the site by taking this survey today! (Bonus: Be entered to win a great tech prize for participating!)

  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now