FAL: Failed to request gap sequence

aliyagmur

I have been using dataguard. Version is 18.3.0.0.0.0. I have some shipped but not applied archivelogs in standby database

select thread#, sequence# from v$archived_log where applied='YES' order by 2;

thread# sequence#

-------- ------------

1 188

1 189

1 190

1 191

1 192

1 193

1 194

When i look at the alert log I can see this log :

FAL: Failed to request gap sequence

GAP - thread 1 sequence 190 - 192

First question: Why does oracle states that applied archived log files are missing?

I configured my dataguard environment like that:

primary.db :

configure archivelog deletion policy to shipped to all standby;

standby.db

configure archivelog deletion policy to applied on standby;

Second question: Daily build have deleted these archivelog logs on both standby and primary servers. I cannot re-apply or re-ship these files. How can i get it work?

Luís Gustavo Lira

Hi, don't you have backup of these archivelogs? For some reason there is a GAP and it needs these archivelogs to resolve the GAP. If it is not possible to restore these archives you will probably need to recreate the standby environment.

aliyagmur

Archivelogs with number of 190 , 191 and 192 are seemed to be applied. But alert log gives an error that these archivelogs are missing:

"FAL: Failed to request gap sequence

GAP - thread 1 sequence 190 - 192"

Why does oracle need these applied archivelogs?

Luís Gustavo Lira

Hi,

I understand your point, I believe that you will need to open a service request to investigate this issue.

I don't know your backup policy, but I would like to emphasize that it is very important to have full and archivelogs backups.

Even using dataguard, you may eventually need to perform a point-in-time recovery and not be able to recover the database.

aliyagmur

I have been using sqlite and postgresql databases. I can get any information easily. Here, it is just some words.