Reset a secret after backup and restore of Data Virtualization

After you run a backup and restore, you might encounter errors in which security processing fails because of password invalidation.

Symptoms

This issue occurs if there is a mismatch of the password from the /secrets/db2instancepwd/password command, which is generated and mounted by the db2uoperator, versus the password that the Db2 security plug-in has in the users.json file.

Resolving the problem

Change to the project where Data Virtualization pods are installed.
```
oc project ${PROJECT_CPD_INST_OPERANDS}
```
Log in to the Data Virtualization head pod.
```
oc rsh c-db2u-dv-db2u-0 bash
```
Switch to the Data Virtualization database instance owner db2inst1.
```
su - db2inst1
```

Extract the Db2 instance password.

PLAINTEXT_PASSWORD=$(cat /secrets/db2instancepwd/password)

Encrypt the new password.

new_hashed_password=$(/sec_plugin/pwgen -gen $PLAINTEXT_PASSWORD)

Extract the previous password.

old_hashed_password=$(cat /mnt/blumeta0/db2_config/users.json | python -m json.tool | grep -i '"username": "db2inst1"' -A7 | grep -i 'password' | xargs | cut -d' ' -f 2 | cut -d',' -f 1)

Copy the /mnt/blumeta0/db2_config/users.json file.

cp /mnt/blumeta0/db2_config/users.json /mnt/PV/versioned/db2_config_users.json

Update the /mnt/blumeta0/db2_config/users.json file by searching for the value of old_hashed_password parameter from step 6 and replacing it with value of new_hashed_password parameter from step 5.
Verify that Db2 can connect to the Db2 Big SQL user db2inst1 with the following command.
```
db2 connect to bigsql user db2inst1 using $(cat /secrets/db2instancepwd/password)
```

Repeat steps 1 - 8 for the following secrets.

cacheadmin

Run the following command to extract the previous password.

cat /mnt/blumeta0/db2_config/users.json | python -m json.tool | grep -i '"username": "cacheadmin"' -A7 | grep -i 'password' | xargs | cut -d' ' -f 2 | cut -d',' -f 1

Find the new password from the secret.

cat /secrets/cacheadminpwd/password

dmcuser

Run the following command to extract the previous password.

cat /mnt/blumeta0/db2_config/users.json | python -m json.tool | grep -i '"username": "dmcuser"' -A7 | grep -i 'password' | xargs | cut -d' ' -f 2 | cut -d',' -f 1

Find the new password from the secret.

cat /secrets/dmcuserpwd/password