NMAP Port States

From Operating System point of view, port can have only two states either Open or Close.  Irrespective of port state from OS views, NMAP detects six type of port states and these states are listed as below Open =>This state is same as Operating System open state. If any port is Open then it will accept… Read More »

Solaris Service states

This is my first post on Solaris. I am sharing my knowledge on service management part of Solaris. Command given in this article is tested on Solaris 10 and Solaris 11. Solaris services are managed through SMF (Service Management Facility). SMF is completely different from init.d style services. There are a few commands such as… Read More »

Heartbleed & KRL

On 7th April, Heartbleed(CVE-2014-0160) shook both the tech-savvy world and the end-users alike. Majority of us use OpenSSL for one or the other reason. If it’s any version of OpenSSL from 1.0.1 through 1.0.1f, released between December 2011 & April 2014, then consider that you have already got compromised with security keys, private keys, passwords… Read More »

OpenStack Storage Types

There are multiple enterprise class storage solutions available such as storage solution from EMC, IBM etc.  Other than enterprise class storage solutions there are variety of storage need exist with varying performance and price range. In Cloud storage environment, Object  Storage and Block Storage two storage category making trends now a days. Object Storage Vs… Read More »

Two Factor Authentication in SSH

Most of us used either password based authentication or public key based authentication while accessing server through ssh protocol.  Password based authentication is default authentication mechanism for ssh. We just have to enable sshd service on server.  For public key based authentication we have to generate private-public key pair.  We covered key based authentication in this… Read More »

Category: SSH

OpenStack Tenant

A OpenStack cloud system suppose to be used by multiple users. A role based access system has been adopted on OpenStack which control access to the shared resource. Roles control the action a user can take. You can say that each tenant is a individual resource container. Let us understand this through an example. I… Read More »

key based ssh authentication (Cygwin)

We all know now that Once installed, Cygwin opportune us to treat the local windows machine Linux Way (http://linuxmantra.com/2014/01/cygwin-openssh-mintty-ssh-client.html) . And a step forward is then to apply the very known public/Private key authentication on Cygwin in exact Linux-to-Linux way (explained @ http://linuxmantra.com/2009/09/ssh-using-privatepublic-key.html). So how actually is Cygwin treating my local machine… Now Using Cygwin-Openssh… Read More »

Category: SSH

Cygwin-openssh-mintty (SSH Client)

Never thought, I would look for alternatives to Putty  & PSM: Putty Session Manager. Cygwin-Openssh-Mintty offers a brilliant option from amongst many other marvels like “MobaXterm” & SecureCRT (Licensed)… Most of us still connect to Linux Machine via ssh-client on a Windows/Mac, to say atleast in office. And I’m no exception. For this I depend… Read More »

Category: SSH

Sysstat Package, sar, sadf, iostat, mpstat, pidstat…

Starts with #sar –options: Dare not try “# sar [-A]”…try and see!!! This will throw at you a multiscreen info and you’ll get lost…hmm…because it contains everything so let’s rather look for our specific need. SYNTAX: to recap the syntax. For live and running stats For analysis of data stored, by sa1, for today until… Read More »