La sauvegarde de l’image de machine virtuelle Avamar prend parfois plus de temps en raison de l’utilisation de nbd au lieu de hotadd

L’heure d’achèvement d’une sauvegarde d’image VMware Avamar est incohérente.

Parfois, la sauvegarde se termine rapidement.

2017-09-21 05:15:08 avtar Info <5156>: Backup #223 timestamp 2017-09-21 05:15:08, 0 files, 925.0 GB (0 files, 352.2 GB, 38.07% new)
2017-09-21 05:15:08 avtar Info <6083>: Backed-up 925.0 GB in 192.63 minutes: 288 GB/hour (0 files/hour)
2017-09-21 05:15:08 avtar Info <7883>: Finished at 2017-09-21 05:15:08 CEST, Elapsed time: 0003h:12m:37s

Les jours « lents », la sauvegarde prend beaucoup plus de temps. Celui ci-dessous prend 24 heures.

2017-09-23 02:10:04 avtar Info <5156>: Backup #224 timestamp 2017-09-23 02:10:04, 0 files, 925.0 GB (0 files, 334.5 GB, 36.16% new)
2017-09-23 02:10:04 avtar Info <6083>: Backed-up 925.0 GB in 1447.94 minutes: 38 GB/hour (0 files/hour)
2017-09-23 02:10:04 avtar Info <7883>: Finished at 2017-09-23 02:10:04 CEST, Elapsed time: 0024h:07m:56s

Les sauvegardes ont des tailles et un taux de modification similaires. Les deux s’exécutent en tant que « sauvegarde complète synthétique ». Les logs indiquent que la sauvegarde la plus rapide utilise « hotadd »

2017-09-21 02:03:06 avvcbimage Info <0000>: Connected with hotadd transport to virtual disk [XXXXX] XXXXXXXX.vmdk. Time to connect: 35082 msecs

La sauvegarde la plus lente signale un problème de connexion à l’aide de hotadd. Il revient à l’utilisation de nbd.

2017-09-22 02:13:22 avvcbimage Info <12006>: hotadd transport is recommended for faster backups and restores and less exposure to network routing, firewall and SSL certificate issues. 
2017-09-22 02:13:22 avvcbimage Info <12007>: One or more of these items may be preventing use of hotadd transport with this VM: 
2017-09-22 02:14:03 avvcbimage Info <12013>: Check that the VM being backed up is in the same datacenter as the backup proxy VM. Hotadd transport cannot cross a Datacenter boundary. . . . 
2017-09-22 02:13:22 avvcbimage Info <0000>: Connected with nbd transport to virtual disk [XXXXX] XXXXXXX.vmdk. Time to connect: 353256 msecs

Chaque jour, la sauvegarde utilisait un proxy différent.

Sauvegarde rapide :

2017-09-21 02:00:09 avvcbimage Info <18672>: proxy VM Instance name is: xxxxx-proxy-8 

Sauvegarde plus lente :

2017-09-22 02:00:15 avvcbimage Info <18672>: proxy VM Instance name is: xxxxx-proxy-2 

Le proxy utilisé le 21 septembre n’était pas disponible le 22 septembre.
La sauvegarde utilisait un autre proxy, qui présentait des problèmes de configuration.
Lors de l’utilisation de ce proxy différent, il n’a pas pu tirer parti du mode de transport « hotadd » plus rapide.

Le log recommande ce qu’il faut vérifier si le transport hotadd ne peut pas être utilisé.

Si la configuration de la machine virtuelle n’a pas été modifiée, vérifiez les vérifications de configuration liées au proxy.
 

2017-09-22 02:13:22 avvcbimage Info <12007>: One or more of these items may be preventing use of hotadd transport with this VM:
2017-09-22 02:14:03 avvcbimage Info <12008>:  Check that the backup proxy VM(127.0.0.2,xxxx-avpro4,10.10.8.53,10.10.7.53) is deployed on an ESX(i) host that has a path to the storage holding the virtual disk being backed up ([XXXXXXXX] XXXXX.vmdk). Also check that the proxy is configured to protect this datastore
2017-09-22 02:14:03 avvcbimage Info <12009>:  Check that the vmfs holding the backup proxy VM has a total capacity equal to the size of the largest virtual disk being backed up. (Capacity merely has to be present - Free space can be less than this amount)
2017-09-22 02:14:03 avvcbimage Info <12010>:  Check that the vmfs holding the backup proxy VM is formatted with a vmfs block size which supports the size of the largest virtual disk being backed up
2017-09-22 02:14:03 avvcbimage Info <12011>:  Check that the VM being backed up has no virtual hard disks designated as independent
2017-09-22 02:14:03 avvcbimage Info <12012>:  Check that the VM being backed up has no IDE virtual hard disks, usually an artifact of a P2v conversion - use SCSI virtual disks instead
2017-09-22 02:14:03 avvcbimage Info <12013>:  Check that the VM being backed up is in the same datacenter as the backup proxy VM. Hotadd transport cannot cross a Datacenter boundary.
2017-09-22 02:14:03 avvcbimage Info <12014>:  Check that no VMs, and no vmdk's within the vCenter have the same name as those associated with the VM being backed up. (unusual but possible)

Pour plus d’informations sur les modes de transport possibles, voir :
https://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vddk.pg.doc_50%2FvddkDataStruct.5.5.html