[Ovirt-devel] [PATCH] Add host state field

[Scott Seago]

Ian Main wrote:
> This patch adds a new column to the hosts table named 'state' which is
> updated via host-status to "available" or "unavailable" based on whether
> it is reachable.  I'm hoping the UI folks can incorporate this fairly
> easily.
>
> It also quiets down host-status and makes it so it only kicks taskomatic
> when the state of a vm needs changing.
>
> Signed-off-by: Ian Main <imain at redhat.com>
> ---
>  wui/src/db/migrate/002_create_hosts.rb |    1 +
>  wui/src/host-browser/host-browser.rb   |    5 ++++-
>  wui/src/host-status/host-status.rb     |   22 ++++++++++++++++------
>  3 files changed, 21 insertions(+), 7 deletions(-)
>
> diff --git a/wui/src/db/migrate/002_create_hosts.rb b/wui/src/db/migrate/002_create_hosts.rb
> index e8b26f2..3e36738 100644
> --- a/wui/src/db/migrate/002_create_hosts.rb
> +++ b/wui/src/db/migrate/002_create_hosts.rb
> @@ -30,6 +30,7 @@ class CreateHosts < ActiveRecord::Migration
>        t.integer :is_disabled
>        t.integer :hardware_pool_id, :null => false
>        t.integer :lock_version,     :default => 0
> +      t.string  :state
>      end
>  
>      execute "alter table hosts add constraint fk_host_pools
> diff --git a/wui/src/host-browser/host-browser.rb b/wui/src/host-browser/host-browser.rb
> index ada5ee1..e127ddb 100755
> --- a/wui/src/host-browser/host-browser.rb
> +++ b/wui/src/host-browser/host-browser.rb
> @@ -110,7 +110,10 @@ class HostBrowser
>                      "arch"            => host_info['ARCH'],
>                      "memory_in_mb"    => host_info['MEMSIZE'],
>                      "is_disabled"     => 0,
> -                    "hardware_pool"   => HardwarePool.get_default_pool).save
> +                    "hardware_pool"   => HardwarePool.get_default_pool,
> +                    # Let host-status mark it available when it
> +                    # successfully connects to it via libvirt.
> +                    "state"           => "unavailable").save
>              rescue Exception => error
>                  puts "Error while creating record: #{error.message}"
>              end
> diff --git a/wui/src/host-status/host-status.rb b/wui/src/host-status/host-status.rb
> index d146c74..41638da 100755
> --- a/wui/src/host-status/host-status.rb
> +++ b/wui/src/host-status/host-status.rb
> @@ -103,15 +103,18 @@ loop do
>    hosts = Host.find(:all)
>    hosts.each do |host|
>      
> -    puts "checking host" + host.hostname
> -
>      begin
>        conn = Libvirt::open("qemu+tcp://" + host.hostname + "/system")
>      rescue
>        # we couldn't contact the host for whatever reason.  Since we can't get
>        # to this host, we have to mark all vms on it as disconnected or stopped
>        # or such.
> -      puts "Failed to contact host " + host.hostname + "; skipping for now", $!
> +      if host.state != "unavailable"
> +        puts "Updating host state to unavailable: " + host.hostname
> +        host.state = "unavailable"
> +        host.save
> +      end
> +
>        Vm.find(:all, :conditions => [ "host_id = ?", host.id ]).each do |vm|
>          # Since we can't reach the host on which the vms reside, we mark these
>          # as STATE_UNREACHABLE.  If they come back up we can mark them as
> @@ -121,12 +124,21 @@ loop do
>          # If this causes too much trouble in the UI, this can be changed to
>          # STATE_STOPPED for now until it is resolved of another solution is
>          # brought forward.
> -        kick_taskomatic(Vm::STATE_UNREACHABLE, vm)
> +
> +        if vm.state != Vm::STATE_UNREACHABLE:
> +          kick_taskomatic(Vm::STATE_UNREACHABLE, vm)
> +        end
>        end
>  
>        next
>      end
>  
> +    if host.state != "available"
> +      puts "Updating host state to available: " + host.hostname
> +      host.state = "available"
> +      host.save
> +    end
> +
>      begin
>        vm_ids = conn.list_domains
>      rescue
> @@ -135,8 +147,6 @@ loop do
>        next
>      end
>  
> -    puts vm_ids.length
> -
>      # Here we're going through every vm listed through libvirt.  This
>      # really only lets us find ones that are started that shouldn't be.
>      vm_ids.each do |vm_id|
>   
ok, I think this is fine. I was initially concerned that there might be 
some confusion with the 'state' and 'is_disabled' fields, but they 
actually serve different purposes. setting 'is_disabled' to 1 is an 
admin-defined state which prevents new VMs from being started on the host.

ack

Scott