ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

System Package Manager for Linux

Updated on August 18, 2013
Daffitt profile image

With a BS degree in Technical Management, I hope to provide useful and relevant articles on topics related to various technologies.

Start the KDE Desktop in Linux

Source

The Task at Hand

In my college course "Introduction To Linux Administration", we were presented with the task of answering five questions related to packages on a Linux server, network monitoring, and port scanning of common ports.

KPackage – Package Manage

The Package Manager displays all of the packages installed on your Linux system.
The Package Manager displays all of the packages installed on your Linux system. | Source

What Packages Are On My Server?

The first question was "How do we find out what packages are installed on our Linux server?

It seems that most students were listing the command prompt dpkg –l | less to get a list of packages installed on the server. I personally prefer the “visual” method of doing things, so I chose to figure it out using the GUI (Graphic User Interface) using the KDE Desktop environment. So here’s what I did…

Once logged into the KDE environment, I selected System, and then KPackage – Package Manager as shown below. Then the Package Manager shows all of the packages that are installed on my server. This is very similar to the concept of the Control Panel’s Add/Remove feature in Microsoft Windows 95 through Windows 7.

What to Get Rid Of:

As one who prefers the convenience of a GUI, I personally enjoy having access to all of the fun and nifty “toys” that are included in a GUI like the KDE. However, in a server situation, the purpose of the server is not to have fun, but to serve up whatever it is that the server is intended to serve up. Be that files, applications, web pages, email, or what have you, the idea is that the only thing the server should be running is what it absolutely needs to do its job as a server. This means that all Games, Extra Editors, Graphic design products, Sound and Video programs, etc. would have to go; especially the games.

The netStat Command:

What is the netStart command, and what are some of the parameters you can use with the netStart command?

The netstat program is a network activity management system. It allows you to manage, track and report on how the network is interacting with your system through the ports that carry data in and out of your server. It is currently installed on our VM and could easily be installed or updated using “Sudo apt-get install netstat.exe”.

Some of the common parameters you can use with netstat are…

  • -a            Show ALL ports
  • -t             Show ports listening/connected to TCP
  • -u            Show ports listening/connected to UDP
  • -r             To display the routing table

…and many more.

The nMap Command:

Nmap is a utility that is not installed on our VM, and is used by both administrators and hackers to scan the ports of a host computer to see what vulnerabilities there might be. As I described in an older post, a port can have one of three different states when a scanner or other program comes poking around. If the port is OPEN, then a hacker is inevitably going to walk right in. If the port is CLOSED, the hacker might walk away, but may also try to break the door down to see what he/she can get to. However, if the port is STEALTH, then it’s as though the port doesn’t even exist, because it just ignores the request coming in, and refuses to send back any signal. This mode would most likely cause the intruder to move on to the next port (or host).

The powerful feature of nmap, is its ability to use multiple methods of scanning in order to circumvent a firewall thereby gaining access to the system by connecting to its ports, and subsequently, its listening applications.

Although in this class we don’t have any need for such a utility, if you wanted to install it, you would use the command… sudo apt-get install nmap.


Some Standard Ports

There are about 65,535 internet ports on a computer. That’s a lot of potential doors and windows that an intruder can use to get at your stuff. However, the first 1,023 ports are of certain concern because those are the common ports used most for applications that listen for connection requests in order to make use of network services. Here are a few of the most common ports…

  • 21 FTP – File Transfer Protocol
  • 23 Telnet Services
  • 25 SMTP – Outgoing Email
  • 80 HTTP – Hypertext Transfer Protocol for the World Wide Web
  • 110 POP3 – Incoming Email
  • 113 IDENT – Identification Protocol used for Authentication Services
  • 139 NetBIOS – for file sharing activities
  • 443 HTTPS – Hypertext Transfer Protocol over the (SSL) Secure Socket Layer

The reason these “common” ports pose a threat is mainly because they are common. They are so well known (especially by hackers), and used by the most common applications that we all use, that they become tasty morsels for a hacker to nibble at.


Comments

Submit a Comment

No comments yet.

working

This website uses cookies

As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://hubpages.com/privacy-policy#gdpr

Show Details
Necessary
HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
LoginThis is necessary to sign in to the HubPages Service.
Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
AkismetThis is used to detect comment spam. (Privacy Policy)
HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
Features
Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
MavenThis supports the Maven widget and search functionality. (Privacy Policy)
Marketing
Google AdSenseThis is an ad network. (Privacy Policy)
Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
Index ExchangeThis is an ad network. (Privacy Policy)
SovrnThis is an ad network. (Privacy Policy)
Facebook AdsThis is an ad network. (Privacy Policy)
Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
AppNexusThis is an ad network. (Privacy Policy)
OpenxThis is an ad network. (Privacy Policy)
Rubicon ProjectThis is an ad network. (Privacy Policy)
TripleLiftThis is an ad network. (Privacy Policy)
Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
Statistics
Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)