Presenters: Chris Wahl and Jason Nash
Both Chris and Jason are very well known in the virtualization industry for their IT expertise and it was great to receive some deep dive information on vSphere distributed switch. They both also hold a dual vCDX (VMware Design Expert) certification
Chris and Jason dived right into their session truly making it a deep dive. For those professionals who have worked with vSphere distributed switches a lot there wasn’t too much but they could always pay attention to best practices and design tips.
Each ESX host keeps local database that describes vDS /etc/vmware/dvsdata.db and it allows ESXi to run vDS as a simple vSwitch when vCenter is down.
Recommendation – Use Elastic ports – don’t set ports manually. For e.g. some people prefer to set their vDS configuration to specific ports instead of using Elastic Ports. Unless you have a pretty good technical reason this is not required.
vDS Quick tips
- Use 802.1Q tags for port groups (don’t use native tagging)
- Atleast 2 vmnics (uplinks) perVDS
- A 2 x 10GbE configuration can work fine
- Put QoS tagging in VDS or physical, not both
- Use descriptive naming everywhere (e.g. use vlan, subnet, and possibly application)
Real world use cases
- Migration VSS to VDS
- Mixing 1Gb and 10Gb links inside one distributed switch
- Handling vMotion saturation
- Controlling vSphere Replication bandwidth
- Doing QoS tagging
- Load based teaming vs Link Aggregation
Don’t try and pin any traffic to one specific uplink
Rename uplinks and use all uplinks in the same way – e.g. with physical links
Multiple vMotion host saturation
In vDS Port Group settings —> traffic shaping —> ingress and Egress shaping can avoid saturation- DRS may cause vMotion saturation.
- Egress – goes in the host. leaving vDS to the host
- Ingress – goes out of the host
Set the average bandwidth and peak bandwidth to the same value. Using QoS we can control traffic shaping
NIOC —-> use this feature which is available under Networking -> Select Port Group —> manage – resource allocation.
If you have more bandwidth during the evening and less during the day you can change traffic direction.
Priority based Flow Control – try to use in UCS PFC – 802.1Qbb (use within vDS)
QoS tips (ideal to use on 10Gb network)
KISS – it solves contention
Pick a place to tag traffic – virtual or physical (don’t do it at both places)
Don’t enforce QoS in many ways
Use clearly defined tagging
Edit resource pool and layer 2 QoS is available there. Also Traffic filtering and marking available in the Port Group setting in web client
A few slide pictures that I took at the session –