12.4. Vérification de la compatibilité de l'unité centrale de l'hôte pour la migration des machines virtuelles

Procédure

1. Sur l'hôte source, obtenez les caractéristiques de son processeur et collez-les dans un nouveau fichier XML, tel que domCaps-CPUs.xml.

   # virsh domcapabilities | xmllint --xpath "//cpu/mode[@name='host-model']" - > domCaps-CPUs.xml

2. Dans le fichier XML, remplacez les balises <mode> </mode> par <cpu> </cpu>.

3. Optional: Vérifiez que le contenu du fichier domCaps-CPUs.xml ressemble à ce qui suit :

   # cat domCaps-CPUs.xml
   
       <cpu>
             <model fallback="forbid">Skylake-Client-IBRS</model>
             <vendor>Intel</vendor>
             <feature policy="require" name="ss"/>
             <feature policy="require" name="vmx"/>
             <feature policy="require" name="pdcm"/>
             <feature policy="require" name="hypervisor"/>
             <feature policy="require" name="tsc_adjust"/>
             <feature policy="require" name="clflushopt"/>
             <feature policy="require" name="umip"/>
             <feature policy="require" name="md-clear"/>
             <feature policy="require" name="stibp"/>
             <feature policy="require" name="arch-capabilities"/>
             <feature policy="require" name="ssbd"/>
             <feature policy="require" name="xsaves"/>
             <feature policy="require" name="pdpe1gb"/>
             <feature policy="require" name="invtsc"/>
             <feature policy="require" name="ibpb"/>
             <feature policy="require" name="ibrs"/>
             <feature policy="require" name="amd-stibp"/>
             <feature policy="require" name="amd-ssbd"/>
             <feature policy="require" name="rsba"/>
             <feature policy="require" name="skip-l1dfl-vmentry"/>
             <feature policy="require" name="pschange-mc-no"/>
             <feature policy="disable" name="hle"/>
             <feature policy="disable" name="rtm"/>
       </cpu>

4. Sur l'hôte de destination, utilisez la commande suivante pour obtenir les caractéristiques de son processeur :

   # virsh domcapabilities | xmllint --xpath "//cpu/mode[@name='host-model']" -
   
       <mode name="host-model" supported="yes">
               <model fallback="forbid">IvyBridge-IBRS</model>
               <vendor>Intel</vendor>
               <feature policy="require" name="ss"/>
               <feature policy="require" name="vmx"/>
               <feature policy="require" name="pdcm"/>
               <feature policy="require" name="pcid"/>
               <feature policy="require" name="hypervisor"/>
               <feature policy="require" name="arat"/>
               <feature policy="require" name="tsc_adjust"/>
               <feature policy="require" name="umip"/>
               <feature policy="require" name="md-clear"/>
               <feature policy="require" name="stibp"/>
               <feature policy="require" name="arch-capabilities"/>
               <feature policy="require" name="ssbd"/>
               <feature policy="require" name="xsaveopt"/>
               <feature policy="require" name="pdpe1gb"/>
               <feature policy="require" name="invtsc"/>
               <feature policy="require" name="ibpb"/>
               <feature policy="require" name="amd-ssbd"/>
               <feature policy="require" name="skip-l1dfl-vmentry"/>
               <feature policy="require" name="pschange-mc-no"/>
       </mode>

5. Ajoutez les caractéristiques de l'unité centrale obtenues de l'hôte de destination au fichier domCaps-CPUs.xml de l'hôte source. Remplacez à nouveau les balises <mode> </mode> par <cpu> </cpu> et enregistrez le fichier.

6. Optional: Vérifiez que le fichier XML contient à présent les caractéristiques de l'unité centrale des deux hôtes.

   # cat domCaps-CPUs.xml
   
       <cpu>
             <model fallback="forbid">Skylake-Client-IBRS</model>
             <vendor>Intel</vendor>
             <feature policy="require" name="ss"/>
             <feature policy="require" name="vmx"/>
             <feature policy="require" name="pdcm"/>
             <feature policy="require" name="hypervisor"/>
             <feature policy="require" name="tsc_adjust"/>
             <feature policy="require" name="clflushopt"/>
             <feature policy="require" name="umip"/>
             <feature policy="require" name="md-clear"/>
             <feature policy="require" name="stibp"/>
             <feature policy="require" name="arch-capabilities"/>
             <feature policy="require" name="ssbd"/>
             <feature policy="require" name="xsaves"/>
             <feature policy="require" name="pdpe1gb"/>
             <feature policy="require" name="invtsc"/>
             <feature policy="require" name="ibpb"/>
             <feature policy="require" name="ibrs"/>
             <feature policy="require" name="amd-stibp"/>
             <feature policy="require" name="amd-ssbd"/>
             <feature policy="require" name="rsba"/>
             <feature policy="require" name="skip-l1dfl-vmentry"/>
             <feature policy="require" name="pschange-mc-no"/>
             <feature policy="disable" name="hle"/>
             <feature policy="disable" name="rtm"/>
       </cpu>
       <cpu>
             <model fallback="forbid">IvyBridge-IBRS</model>
             <vendor>Intel</vendor>
             <feature policy="require" name="ss"/>
             <feature policy="require" name="vmx"/>
             <feature policy="require" name="pdcm"/>
             <feature policy="require" name="pcid"/>
             <feature policy="require" name="hypervisor"/>
             <feature policy="require" name="arat"/>
             <feature policy="require" name="tsc_adjust"/>
             <feature policy="require" name="umip"/>
             <feature policy="require" name="md-clear"/>
             <feature policy="require" name="stibp"/>
             <feature policy="require" name="arch-capabilities"/>
             <feature policy="require" name="ssbd"/>
             <feature policy="require" name="xsaveopt"/>
             <feature policy="require" name="pdpe1gb"/>
             <feature policy="require" name="invtsc"/>
             <feature policy="require" name="ibpb"/>
             <feature policy="require" name="amd-ssbd"/>
             <feature policy="require" name="skip-l1dfl-vmentry"/>
             <feature policy="require" name="pschange-mc-no"/>
       </cpu>

7. Utilisez le fichier XML pour calculer la ligne de base de la fonctionnalité CPU pour la VM que vous avez l'intention de migrer.

   # virsh hypervisor-cpu-baseline domCaps-CPUs.xml
   
       <cpu mode='custom' match='exact'>
         <model fallback='forbid'>IvyBridge-IBRS</model>
         <vendor>Intel</vendor>
         <feature policy='require' name='ss'/>
         <feature policy='require' name='vmx'/>
         <feature policy='require' name='pdcm'/>
         <feature policy='require' name='pcid'/>
         <feature policy='require' name='hypervisor'/>
         <feature policy='require' name='arat'/>
         <feature policy='require' name='tsc_adjust'/>
         <feature policy='require' name='umip'/>
         <feature policy='require' name='md-clear'/>
         <feature policy='require' name='stibp'/>
         <feature policy='require' name='arch-capabilities'/>
         <feature policy='require' name='ssbd'/>
         <feature policy='require' name='xsaveopt'/>
         <feature policy='require' name='pdpe1gb'/>
         <feature policy='require' name='invtsc'/>
         <feature policy='require' name='ibpb'/>
         <feature policy='require' name='amd-ssbd'/>
         <feature policy='require' name='skip-l1dfl-vmentry'/>
         <feature policy='require' name='pschange-mc-no'/>
       </cpu>

8. Ouvrez la configuration XML de la VM que vous souhaitez migrer et remplacez le contenu de la section <cpu> par les paramètres obtenus à l'étape précédente.

   # virsh edit VM-name

9. Si la VM est en cours d'exécution, redémarrez-la.

   # virsh reboot VM-name