Transparent Service Migration to the Cloud Clone existing VMs to CloudStack/OpenStack templates without user downtime. CloudOpen Seattle 2015

Transcription

1 Transparent Service Migration to the Cloud Clone existing VMs to CloudStack/OpenStack templates without user downtime CloudOpen Seattle 2015

2 #whoami Name: Tim Mackey Current roles: XenServer Community Manager and Evangelist; occasional coder Cool things I ve done Designed laser communication systems Early designer of retail self-checkout machines Embedded special relativity algorithms into industrial control system Find me SlideShare: slideshare.net/timmackey LinkedIn: GitHub:

3 Define VM Migration What people think VM moves from source host to destination Template Why it doesn t work to the cloud Incompatible host micro-architecture Lack of control over networking Do we really want a VM_HALT? Long distance ARP Really need template migration Template Template

4 CloudStack view of Templates

5 Template Management in CloudStack My first template Existing VM or appliance in VHD format compression optional Need to have HTTP server Set secstorage.allowed.internal.sites if private cloud Creation options Register template in UI Templates Register Template Upload using registertemplate API Clone from CloudStack instance Stop instance View Volumes Create Template

6 Key Template Attributes Obvious Hypervisor Operating system type Zone Not so obvious IsDynamicallyScalable Hypervisor tools PasswordEnabled CloudStack sets root pwd SSHKeyEnabled Can post configure RequiresHVM Defines virtualization mode

7 VM Password and SSH Key Management Challenges Obtain information from Virtual Router IP is obtained from leases Scripts use wget Assumes sysinit not systemd What to fix varies by OS? CentOS 7 defaults to curl not wget CentOS 7 is systemd need unit files CentOS 7 may use NetworkManager

8 OpenStack view of Templates

9 Template Management in Horizon and Glance My first template Existing VM or appliance in hypervisor specific disk format XenServer: VHD format with file named 0.VHD and tgz Creation options Register image in Horizon System->Images->Create Image Upload using Glance API Clone from running instance Compute->Instances->Create Snapshot

10 Key Image Attributes Obvious (x-image-meta-) Owner Flavor information (Disk and RAM) Region Not so obvious (x-image-meta-property) hypervisor_type Xen for XenServer vm_mode PV vs. HVM os_type Linux or Windows for swap space

11 Handling Critical Initial VM Configuration Obtain information from instance configuration drive ISO 9660 or VFAT drive assigned to instance at boot Supported with libvirt, XenServer, vsphere and Hyper-V Works with custom scripts and cloud-init Using a configuration drive Specify per instance on nova boot --config-drive true Force for all instances in nova config force_config_driver=true Pass both meta information and userdata

12 How the tooling works

13 Packer is Awesome!!

14 Core Packer Concepts Builder Responsible for creation of VM image Connects to virtual infrastructure Default supports vsphere, OpenStack, AMI, VirtualBox, QEMU, Docker No XenServer needed to fix that ;) Provisioner Runs post-build activities Post-Processor Takes VM image artifact and transforms it In our case upload to CloudStack or OpenStack needed to fix that too ;)

15 Key Activities Occurring During Template Build from ISO 1. Download ISO into ISO SR (if not already present) 2. Attach ISO to VM object and boot 3. Instruct installer to user kickstart file 4. Installer does its thing and shuts VM down 5. Upon shutdown, swap installer ISO for XenServer tools ISO 6. Install ISO and shutdown 7. Detect shutdown and run Provisioners 8. Export and import into the cloud as template

16 xenserver-iso builder Creates a new XenServer image from an ISO Key parameters Host connection ISO location Boot commands Artifact output type xva, vdi_raw, vhd, vhd_raw Known limitations Linux only (uses SSH) Requires NFS shared storage for export

17 xenserver-vm builder Creates a new XenServer image from existing running VM Key parameters Host connection VM name Cleanse command Cleanse scripts Artifact output type xva, vdi_raw, vhd, vhd_raw Known limitations Linux only (uses SSH) Requires NFS shared storage for export

18 cloudstack-xenserver post-processor Creates a new CloudStack template from xenserver builders Key parameters CloudStack API keys Zone, OS type Script configuration Artifact input xenserver-iso, xenserver-vm

19 openstack-xenserver post-processor Creates a new OpenStack Glance image from xenserver builders Key parameters Keystone URL and credentials Project name, region, and instance name Script configuration Artifact input xenserver-iso, xenserver-vm

20 Key Activities Occurring During Service Migration 1. Snapshot of existing VM to minimize downtime 2. Detect if VM is PV or HVM and flag accordingly 3. Copy snapshot to NFS SR to collapse any snapshot chains 4. Connect primary network to HIMN to ensure no machine collision 5. Use VNC to reconfigure network and connect to XenServer DHCP server 6. Copy and run cleanse scripts which shutdown clone when complete 7. Detect shutdown and run Provisioners 8. Export and import into cloud as template

21 Demo time. 10 minutes to move a live service to the cloud (network willing)

22 The Service to Migrate Piwigo

23 The Original Topology

24 The Cloud Topology with Original Data Store Intact

25 Bringing Migration all Together with an ADC Users My Cloud

26 Confirm the Migration and Iterate 1. Verify service migrated correctly 2. Iterate and resolve any issues 3. Scale the service Let s add more capacity 4. Add service to original load balancer Don t forget to adjust session weights 5. Decommission original service

27 Questions?

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