Month: May 2016

Change the user password or unlock the user account in sqlplus.

1. Connect as sysdba from the command line:

sqlplus / as sysdba

2. List all users:

select username from dba_users;

3. Check whether the user account is locked:

select * from dba_users where username = 'USERNAME';

4. If locked, use this command to unlock the account:

alter USER USERNAME account unlock;

5. To change the user’s password type the following command:

password USERNAME;

SSL – Check whether a private key matches a certificate or whether a certificate matches a certificate signing request (CSR).

Check whether a private key matches a certificate or whether a certificate matches a certificate signing request (CSR). If you are receiving an error that the private doesn’t match the certificate or that a certificate that you installed to a site is not trusted, try one of these commands. Check an MD5 hash of the public key to ensure that it matches with what is in a CSR or private key.

root# openssl x509 -noout -modulus -in certificate.crt | openssl md5
root# openssl rsa -noout -modulus -in privatekey.key | openssl md5
root# openssl req -noout -modulus -in csr.csr | openssl md5

For example:
root# openssl req -noout -modulus -in just4testcert_req.csr | openssl md5
(stdin)= 61c59f9a9ddddc032e56fe2e46a91409
root# openssl rsa -noout -modulus -in just4test_server.key | openssl md5
(stdin)= 61c59f9a9ddddc032e56fe2e46a91409

Clear Winbind cache

Clear all Winbind caches and flush Net cache, always take a backup before deleting 😉

Stop the Winbind service and Samba service (if you have it):

root# service winbind stop
root# service smb stop

Clear the Samba Net cache:

root# net cache flush

Delete the Winbind caches:

root# rm –f /var/lib/samba/*.tdb
root# rm –f /var/lib/samba/group_mapping.ldb

Start the Samba (if you have it) and then Winbind services

root# service smb start
root# service winbind start

SSH – PermitRootLogin

PermitRootLogin
Specifies whether root can log in using ssh(1). The argument must be “yes”, “without-password”, “forced-commands-only”, or “no”.
The default is “yes”.
If this option is set to “without-password”, password authentication is disabled for root.
If this option is set to “forced-commands-only”, root login with public key authentication will be allowed, but only if the command option has been specified. Useful for backups 😉 All other authentication methods are disabled for root.
If this option is set to “no”, root is not allowed to log in.
Thus without-password allows root login only with public key authentication.