Zimbra. Postfix_rbl_override.lmdb: No such file or directory

Zimbra. Postfix_rbl_override.lmdb: No such file or directory How to fix Zimbra mail server error: lmdb:/opt/zimbra/conf/postfix_rbl_override is unavailable. open database /opt/zimbra/conf/postfix_rbl_override.lmdb: No such file or directory. To build missing postfix_rbl_override.lmdb file run postmap and zmprov. # /opt/zimbra/common/sbin/postmap /opt/zimbra/conf/postfix_rbl_override # /opt/zimbra/bin/zmprov mcf… Continue Reading

Useful Netcat Examples and Tutorial

Useful Netcat Examples

Useful Netcat Examples In this netcat tutorial you can see useful netcat examples to help you use this powerful tool. Netcat (nc – in short) can be called “Swiss army of knife” in Linux network terminal utilities. Netcat can be… Continue Reading

How To Test Internet Speed On VPS

Linux VPS upload download speed test

How To Test Internet Speed On Linux VPS To get internet speed from command line Linux VPS we can use Python utility from SPEEDTEST – Speedtest-cli. Speedtest-cli is a script developed in Python programming language. Lets download SPEEDTEST utility from… Continue Reading

How To Generate Self-Signed TLS Certificate in Linux

Generate Self-Signed TLS Certificate

How To Generate Self-Signed TLS Certificate TLS (Transport Layer Security)is cryptographic protocol for providing secure communications. To Generate Self-Signed TLS Certificate login as root user. Create certs directory. # mkdir /root/certs # cd /root/certs Generate certificate with openssl command line… Continue Reading

CUDA. Samples: Installed in /home/user/, but missing recommended libraries

NVIDIA CUDA

CUDA. Samples: Installed in /home/user/, but missing recommended libraries After installing CUDA 10.1 in Ubuntu you may have error: Samples: Installed in /home/user/, but missing recommended libraries. Because some CUDA samples use third-party libraries which may not be installed by… Continue Reading