Stateless Computing with UCSM and VMware Auto Deploy - Best Practices

John Kennedy TME SAVTG

Stateless Computing with UCSM and VMware AutoDeploy – Best Practices

© 2010 Cisco and/or its affiliates. All rights reserved. Cisco ConfidentialPresentation_ID 2

What does “Stateless” mean?

Statefull := stuck to the hardware

Maybe the OS is installed on a local disk, that isn’t replicated…

Maybe an Application depends on a burned in identifier, like WWPN or MAC or UUID…

Stateless := free to migrate where needed

Nothing in the hardware prevents the software from running on other hardware

MAC addresses, WWPN, etc. move from machine to machine based on the needs of the business

Stateless vs. Statefull


StorageSME

ServerSME

NetworkSME

Traditional Element Configuration

• Subject matter experts consumed by manual configuration chores

• Serial processes and multiple touches inhibit provisioning speed

• Configuration drift and maintenance challenges

• FC Fabric assignments for HBAs

• RAID settings• Disk scrub actions

• Number of vHBAs• HBA WWN

assignments• FC Boot Parameters• HBA firmware

• Number of vNICs• PXE settings\• NIC firmware• Advanced feature settings

• VLAN assignments for NICs• VLAN tagging config for NICs

• QoS settings• Border port assignment

per vNIC• NIC Transmit/Receive

Rate Limiting

• Remote KVM IP settings• Call Home behavior• Remote KVM firmware

• Server UUID• Serial over LAN settings• Boot order• IPMI settings• BIOS scrub actions• BIOS firmware• BIOS Settings

LAN SAN


Unified, Embedded ManagementAligns People, Policy, and Configuration With Workload

Server Policy…

Storage Policy…

Network Policy…

Virtualization Policy…

Application Profiles…

Subject Matter Experts Define Policies1

StorageSME

ServerSME

NetworkSME

Policies Used to Create

Service Profile Templates

2

Service Profile Templates

Create Service Profiles

3

Associating ServiceProfiles with Hardware

Configures ServersAutomatically

4

Unified Management

Server NameUUID, MAC, WWNBoot InformationLAN, SAN ConfigFirmware Policy






How does Cisco UCS enable stateless computing?

UCS hardware can have any MAC, WWPN, UUID applied to it through software

Choose layout

Then select the layout with the background you would like

Service profile basics


What are the benefits of Stateless Computing?

Simplified provisioning

Upgrades of hardware

Migration to a new datacenterWithout a forklift…

Disaster recovery

Allows migration of server functionality


How does UCS enable stateless computing?

UCS applies a “Service Profile”XML collection of metadata

Service Profile is centralized, for ease of management

Service Profiles can be removed from one server and applied to another

Host OS, Applications, Network and Storage cannot tell the difference

Service Profiles can be created from Service Profile TemplatesRepeatability, ease of management, reliability…

When Template is updated, attached profiles get the updates.

By overriding the servers current WWPN, MAC, UUID, etc.


But Doesn’t VMware enable Stateless Computing?

Server boot from the network, not a SAN or local disk

State data kept in Host Profiles

Allows Elastic Capacity on Demand

Yes, with vSphere AutoDeploy


AutoDeploy Basics


Frailties of vSphere AutoDeploy

Requires DHCP, TFTP, all must be managed

If AutoDeploy server fails, ESXi servers can’t reboot

In the event of a Power outage, AutoDeploy has to be running before ESXi can boot from it.

If AutoDeploy is running in a VM…Chicken? Egg?


New Feature in vSphere 5.1: Statefull AutoDeploy

Allows AutoDeploy to leave a copy of the ESXi server state on a local disk

FlexFlash© , SATA drive, …

If server reboots, and AutoDeploy or vCenter isn’t available, server retains it’s identity.

When AutoDeploy is available, reboot the server, and it is once again stateless.


Does AutoDeploy conflict with Service Profiles?

The two work together… When a Service Profile moves to another server, vCenter and

AutoDeploy don’t see a new MAC or IP addressESXi server retains it’s host profile, and it’s state

When a Service Profile moves to another server, the local disk can be “scrubbed”

Assumes you use a Full Scrub profile in UCS, so be sure you do…

This is an advantage of current servers!


Attributes unique to UCS

The best practice method for autodeploy is to create a deploy rule that is associated with a Service Profile or Service Profile Template so that he infrastructure is consistent for a give deployment.

UCS populates the oemstring variables with profile, template, and system name attributes:

These attributes enable the creation UCS-specific DeployRules!


Best PracticesSpecific to this topic… Make your AutoDeploy, DHCP and TFTP highly available!

Ensure the IPMI address stays with the profileEnables Distributed Power Management

Make DHCP reservation for your Service Profiles

Make individual Host Profiles for each Service Profile

Set your Host Profiles to use Stateless install on local diskFlexFlash is available on C series only

Don’t move B series SP to C series or vice versa


Best PracticesSpecific to this topic… Set your boot order profile to boot from:

CDROM (for troubleshooting)

vNICA (Best to use just one…)

Local Disk

Set your vNIC to use Native VLANOtherwise either DHCP or gPXE will break


In summary

vSphere AutoDeploy 5.1 lets the ESXi server retain state on the local disk

But that’s not good if you want to repurpose that server

You have to scrub the server yourself

The replacement server will have a new MAC, new IP, and won’t look the same to vCenter

But with UCS Service Profiles, the MAC, WWPN, etc. go on whatever server you wish

So your ESXi server remains available after moving to a new piece of hardware


Where can I learn more?

AutoDeploy documentationhttp://bit.ly/OgLlZj

VMware KB article 2005131http://bit.ly/OgLH27

Cisco UCS solutionshttp://www.cisco.com/go/ucs

http://bit.ly/OgLlZj

http://bit.ly/OgLlZj

http://bit.ly/OgLH27

http://bit.ly/OgLH27

http://www.cisco.com/go/ucs


Questions?

Technology

Stateless Computing with UCSM and VMware Auto Deploy - Best Practices