AWS provides no password for the root user. If root is locked out, we use a backdoor login with root privileges through the EC2 Console.
Configure a Backdoor Login
There are cases where root login fails, even after a stop/start of the EC2 instance. A backdoor user login or a rebuild from a snapshot are our options. A user needs a strong password.
Let’s add a user:
(When adding a user, if you get an error, see the fix below)
--> Use your own user and password/ This examle uses "brew". I use the vi editor. adduser brew --> "passwd brew" will add the password if you need to do so manually. vi /etc/sudoers --> at the end of the file add: brew ALL=(ALL) NOPASSWD:ALL --> SHIFT : w! to save SHIFT ZZ to exit <-- cd /home/ec2-user cp -pr .ssh ../SSH_BACKUP
If you get this error when adding a user:
[sss_cache] [sysdb_domain_cache_connect] (0x0010): DB version too old [0.22], expected [0.23] for domain implicit_files!
Higher version of database is expected!
In order to upgrade the database, you must run SSSD.
Removing cache files in /var/lib/sss/db should fix the issue, but note that removing cache files will also remove all of your cached credentials.
Could not open available domains
To fix this, do the following:
cd /var/lib/sss/db rm * sss_cache -E
Then add the backdoor user, or if already created, add the password.
Then add permissions:
usermod -aG adm brew usermod -aG root brew
