Load Sharing and DHCP Server ?

[Danny]

We are maintaining more and more end users with 3-node clusters in load sharing mode. One R80.10 end user has activated the DHCP Server on his three clusternodes and therefore receives dhcp duplicates on his systems caused by all three clusternodes actively responding to dhcp requests.

ClusterXL Load Sharing mode limitations and important notes does not mention any existing limitation for DHCP Server.

The end user could send DHCP requests to the physical IP address of one of his three clusternodes only, but this would mean a loss of redundancy for his DHCP functionality.

WHat would you suggest?

[_Val_]

Danny Jung‌, why LS? Just curious. 

[Danny]

• To share the load. When HA with only one active member isn't capable of handling the entire traffic load then load sharing is one of the options you get, when you have more than two clusternodes available.
• To actively use the investment of three clusternodes and not having two enterprise appliances staying idle in standby mode the entire day.
• and more

[_Val_]

I have to comment on two first bullet points,

In my humble opinion, in practice LS CP clustering on physical nodes brings mode bottlenecks if compared with HA option. In case you have bought 3 cluster members and want to use them all together, the only sensible option is to go for VSLS implementation with 3 or more VSs. 

[G_W_Albrecht]

For DHCP Relay, thre is #3 from sk97566 Certain subnets and hosts behind NAT cannot obtain or renew IP addresses over DHCP in R77:

• Explanation for issue with DHCP and Manual NAT in ClusterXL Load Sharing mode
  

  • DHCP traffic is not configured to be synchronized between cluster members.
  • Stick Decision Function (SDF) is disabled.

But a DHCP Server in LS would need to share IP address information...

[Danny · Accepted solution]

Disabling the DHCP server from the Load Sharing cluster and putting a dedicated DHCP server into place solved our issue.

[KennyManrique]

How does Cloning Group behave on this scenario? Anyone who has tried?

Regards.