Brief Introduction to Zimbra Internal Architecture

In some cases, you might want to recover your data from Zimbra, or you may be curious about how Zimbra manages users and emails behind the scenes. I dug into Zimbra’s nuts and bolts because we lost Zimbra’s local LDAP, which took more than 3 days to fix, so I wanted to share what I… Continue reading Brief Introduction to Zimbra Internal Architecture

How to Configure Iptables in Stateful Mode Properly

Iptables is a software firewall based on Netfilter, in fact it’s a framework for working with Netfilter. Generally firewalls have two modes, stateless and stateful. In this post we will study a brief of how to configure Netfilter in stateful mode. I’m going to assume your linux box is fresh installation and doesn’t have any… Continue reading How to Configure Iptables in Stateful Mode Properly

Enabling LDAP on Linux and local user’s session will interchange with LDAP’s user intermittently

Let’s say you have a central authentication server in a LDAP and you successfully connect your Linux box as a client to LDAP server. Whenever you are using a particular LDAP user to login to your box, your shell get confused and change the LDAP user with a local user of your box┬áintermittently. What is… Continue reading Enabling LDAP on Linux and local user’s session will interchange with LDAP’s user intermittently

After configuring Ubuntu to use LDAP ssh login become too slow

This is a common symptom of mis behaviour of systemd-logind. I couldn’t still find-out what is really happening underneath of this service but if you experience such issues you can try to restart the service using following command sudo service systemd-logind restart and make sure to run this code on the console not just by… Continue reading After configuring Ubuntu to use LDAP ssh login become too slow

How to traceroute a particular IP and Port?

There are sometimes that you want to trace an IP/Host based on a particular port to check if the port is open or not here is how you can do that : traceroute -T -p 25 yoursite.com Breakdown : -T indicates to use TCP instead of UDP -p checks specific port