Thanks Mohib, I managed to find the inum using the ldapsearch provided, created changeAuth.ldif file as suggested, but I got an error:
Finding inum:
```
GLUU.root@id1:/# /opt/opendj/bin/ldapsearch -h localhost -p 1636 -Z -X -D "cn=directory manager" -w '*****' -b "ou=appliances,o=gluu" -s one "objectclass=*" oxAuthenticationMode
dn: inum=@!B6FC.5EF2.F14B.B108!0002!2097.2DD5,ou=appliances,o=gluu
oxAuthenticationMode: super_gluu
```
changeAuth.ldif file:
```
dn: inum=@!B6FC.5EF2.F14B.B108!0002!2097.2DD5,ou=appliances,o=gluu
changetype: modify
delete: oxAuthenticationMode
```
Error:
```
GLUU.root@id1:/# /opt/opendj/bin/ldapmodify -h localhost -p 1389 -D "cn=directory manager,o=gluu" -w ****** -f changeAuth.ldif
Connect Error
Result Code: 91 (Connect Error)
```