The backup administrator configured replication for a VM from Data Center 1 to Data Center 2, which runs every day at 1 a.m. A power surge takes out Data
Center 1 at 7 a.m. and the administrator fails over the replica at 8 a.m. When the power comes back on, the administrator performs the `failback` action at 2 p.m. and checks the state of the original VM. They recognize that not all data is available. What is missing?
The backup replication is configured to run daily at 1 a.m. This means that the most recent replication would have completed at 1 a.m. on the day of the outage. When Data Center 1 experienced a power surge at 7 a.m., any data created or modified between 1 a.m. and 7 a.m. was not replicated to Data Center 2 because the next replication would occur at 1 a.m. the following day. After the failover at 8 a.m., data started being written to the replica. Hence, upon failing back at 2 p.m., the data from 1 a.m. to 7 a.m. is missing, as it was never replicated due to the power outage.
A is correct. There is no data replicated since the last replication at 1:00 a.m. until the 7 a.m. No data exists between 7 a.m and 8 a.m. as the machine is down. At 08:00 new data starts to be written in the new replica. Data loss is between 01:00 am and 07:00 am.
Maybe D is correct Original VM had data from 1 a.m. to 7 a.m. Replica had data from 8 a.m. to 2 p.m. When failback, replica sync different data from 8 a.m. to 2 p.m. to original vm. So, data is missing form 7 a.m. to 8 a.m.
Just can't realize how the data can be written from 7 to 8 on DC1VM if there is no electricity.... If somehow new data is written from 7 to 8 on DC1VM then when the failback process starts at 2 pm veeam should calculate and synchronize the differences between data on DC2VM and DC1VM: DC1VM contains data until 8 am DC2VM contains data until 1 am and from 8 am to 2pm The data saved from 8am to 2pm on DC2VM is transported to he DC1VM which contains data until 8 am (or 7am if data is not written during the power surge) Guess what is missing? May be the data from 7 to 8 am is missing because it was never created or it's created but veeam failback process don't know about it?
Must be A ! Failback synchronise data from replica to production. https://helpcenter.veeam.com/docs/backup/vsphere/failback.html?ver=100
The answer is A. No replication between 1:00 AM - 7:00 AM When I failback I have the data until 1:00 AM + data between 8:00 AM - 2:00 PM
B unfortunally is correct: The difference of the disks from site 1 to site 2 is 1AM to 7AM (7 to 8 nobody worked without light). They worked with the data from 1AM and finished work at 2PM. VMs with data from 1 to 7AM was changed to "NEW VMs" from failover with data only 1AM and 8AM to 2PM.
A is correct. Because: replication is at 1 a.m. All the data from 1 a.m. to 7 a.m. is lost because production VM is taken out by a power surge. New data is written from 8 a.m. to 2 p.m. So, we have lost all the data from replication to 7 a.m. (from 7 a.m. to 8 a.m. no data was written also)
A is correct, Data is lost from the last replication until the failover starts
D. Read the following https://helpcenter.veeam.com/docs/backup/vsphere/failback.html?ver=100
Veeam Backup & Replication calculates the difference between disks of the original VM and disks of the VM replica in the Failover state. Difference calculation helps Veeam Backup & Replication understand what data needs to be transported to the original VM to synchronize it with the VM replica.
It's A, the data loss window is between 1AM to 7AM, that's when to power surge happened e no further data was written, there is no power to feed the servers.
It´s D, since VEEAM is checking the state of the Original VM (which indeed was working until 7 am), the only gap where no Data is written is between 7 an 8. If the VM were completly lost in DC01 at 7 am there would apply the answer A, otherwise Data is still in DC01 at the momment the power outage occurs and comes back.
replica is made at 1:00AM, if the VM dies at 7:00am where do you get the data 1:00AM-7:00AM from?
the data from 1am to 7am is on the original VM because you didnt lost the entire DC, when you failback you sync the replicated VM with the original VM, so you only lost data from 7-8am
correct is A
C. Data from 8 a.m. to 2 p.m. Its the new data generated
It should be D.
I think D is correct.
Answer should be D since this is the window where no data was available replicated between sites. There was no data on ether site during the outage 7am-8am see https://helpcenter.veeam.com/docs/backup/hyperv/failback.html?ver=100
The correct answer should be D, Please see this video that had exactly situation like question, (from 7:00 to 7:30) https://youtu.be/jrSg5oXCmXU?t=420
A is correct