From troubleshooting DNS queries and misbehaving network apps to keeping your configurations and passwords organized, these tools have you covered
Routing issues, slow network applications, DNS resolution problems -- a network administrator has to deal with a host of network nuisances on a daily basis. How do you survive when you're constantly under the gun to fix the problems? Like any other professional, you need a solid set of tools.
Not surprisingly, plenty of options exist in the open source camp. Excellent open source software tools are available to help you keep a close watch over your network, as well as meet many other needs of the busy network manager. From monitoring, troubleshooting, and security analysis tools to utilities for keeping track of IP allocations, passwords, and router configurations, here are my top 10 picks of the most essential open source tools for our network admin toolbox -- all free for the downloading.
This is by no means an exhaustive list of open source networking utilities available, and I've merely touched on their capabilities. Are there other free open source tools that you use regularly but we didn't list here? Leave a comment and let us know!
Top free open source tools for network admins: Dig
DNS problems plague us all, and they're easily overlooked when troubleshooting, so you need a reliable tool that provides detailed information about how users' DNS queries are being resolved. Why not use the tool made by the Internet Systems Consortium, the same group that produces the BIND DNS server software running the majority of DNS servers worldwide? That tool is Dig.
At the heart of it, Dig is a command-line utility that performs DNS queries. That alone is helpful, but Dig can also tell you most everything about the queries and replies -- you'll sometimes need that extra information to determine why you're getting a strange reply from a DNS server. The default output of Dig provides you with all the data you'll require for troubleshooting: reply/error codes from the server, flags used in the query, a reiteration of your query, the answer to your query, how long the query took, which server it received the reply from, and how much data it received in the reply. Dig can be quite useful when you're trying to diagnose slow network applications, by determining how long it takes a computer to get DNS resolution for the application server's domain name.
f you're a longtime user of Nmap but haven't kept up with Nmap news and releases, you'll want to check out the Zenmap GUI's new network topology feature, which lets you create an interactive network map based on information gathered by Nmap. The map begins with localhost at the center and displays all discovered hosts in concentric rings around it, the rings indicating the number of hops away the hosts are. From there you can shift the focus to another host or get more info by clicking a host's icon in the map. The shape of the icon refers to the type of device, and the size indicates the number of open ports.
All this makes Nmap perfect for checking on IP address usage, scanning for security vulnerabilities, and ensuring your firewalls and routers are operating properly.
Top free open source tools for network admins: KeePass
Oh the passwords! How many passwords do we have for all the various servers, switches, routers, and other network gear we have to manage? And when we have to change a password, we must be sure to notify all of the other people who have access to that equipment. A good password management system can save valuable time and spare you a lot of hassle.
Enter KeePass, an encrypted database program to store all of your usernames, passwords, access URLs, and more. You can restrict access to the KeePass database with a password, a key file, or both. The password database is encrypted with either AES or the Twofish encryption algorithm, and not as one contiguous file but in 256-bit chunks -- decrypting a single piece of data nets a cracker little or no useful data. Plus KeePass encrypts all the data in its database, not just the passwords, so your usernames, URLs, and other notes are safe as well.
You can create groups for password records to help organize the info if you have a lot of passwords to track. Groups can have subgroups, subgroups can have subgroups, and so on. A search function helps you quickly find the password record you need.
How do you share the KeePass database with coworkers who are running Mac OS X or some other version of Unix? No problem. KeePass is ported to Windows, Mac OS X, various Linuxes, and popular mobile phone platforms, including iPhone, Android, and BlackBerry. Because the KeePass database is stored in a single file, it's easy to distribute among your NOC team. Did I mention that KeePass is portable, needing no installation on Windows or Mac OS X? You can carry it with you on a USB stick or download it to a computer without leaving any unwanted registry entries or library files.
Already using another password manager? KeePass can import your existing password database in formats from a variety of programs such as Password Keeper, CodeWalletPro, and Password Agent. Other file formats are supported through KeePass plug-ins.
Top free open source tools for network admins: IPplan
We network admins must keep track of which IP addresses we have, which are in use, and which are available to be allocated to the systems administrators who always want yet another IP address for their servers. Are you tracking your IP addresses in an Excel spreadsheet? Well, stop! Get the benefits of using a real database with IPplan.
Not surprisingly, plenty of options exist in the open source camp. Excellent open source software tools are available to help you keep a close watch over your network, as well as meet many other needs of the busy network manager. From monitoring, troubleshooting, and security analysis tools to utilities for keeping track of IP allocations, passwords, and router configurations, here are my top 10 picks of the most essential open source tools for our network admin toolbox -- all free for the downloading.
This is by no means an exhaustive list of open source networking utilities available, and I've merely touched on their capabilities. Are there other free open source tools that you use regularly but we didn't list here? Leave a comment and let us know!
Top free open source tools for network admins: Dig
DNS problems plague us all, and they're easily overlooked when troubleshooting, so you need a reliable tool that provides detailed information about how users' DNS queries are being resolved. Why not use the tool made by the Internet Systems Consortium, the same group that produces the BIND DNS server software running the majority of DNS servers worldwide? That tool is Dig.
At the heart of it, Dig is a command-line utility that performs DNS queries. That alone is helpful, but Dig can also tell you most everything about the queries and replies -- you'll sometimes need that extra information to determine why you're getting a strange reply from a DNS server. The default output of Dig provides you with all the data you'll require for troubleshooting: reply/error codes from the server, flags used in the query, a reiteration of your query, the answer to your query, how long the query took, which server it received the reply from, and how much data it received in the reply. Dig can be quite useful when you're trying to diagnose slow network applications, by determining how long it takes a computer to get DNS resolution for the application server's domain name.
f you're a longtime user of Nmap but haven't kept up with Nmap news and releases, you'll want to check out the Zenmap GUI's new network topology feature, which lets you create an interactive network map based on information gathered by Nmap. The map begins with localhost at the center and displays all discovered hosts in concentric rings around it, the rings indicating the number of hops away the hosts are. From there you can shift the focus to another host or get more info by clicking a host's icon in the map. The shape of the icon refers to the type of device, and the size indicates the number of open ports.
All this makes Nmap perfect for checking on IP address usage, scanning for security vulnerabilities, and ensuring your firewalls and routers are operating properly.
Top free open source tools for network admins: KeePass
Oh the passwords! How many passwords do we have for all the various servers, switches, routers, and other network gear we have to manage? And when we have to change a password, we must be sure to notify all of the other people who have access to that equipment. A good password management system can save valuable time and spare you a lot of hassle.
Enter KeePass, an encrypted database program to store all of your usernames, passwords, access URLs, and more. You can restrict access to the KeePass database with a password, a key file, or both. The password database is encrypted with either AES or the Twofish encryption algorithm, and not as one contiguous file but in 256-bit chunks -- decrypting a single piece of data nets a cracker little or no useful data. Plus KeePass encrypts all the data in its database, not just the passwords, so your usernames, URLs, and other notes are safe as well.
You can create groups for password records to help organize the info if you have a lot of passwords to track. Groups can have subgroups, subgroups can have subgroups, and so on. A search function helps you quickly find the password record you need.
How do you share the KeePass database with coworkers who are running Mac OS X or some other version of Unix? No problem. KeePass is ported to Windows, Mac OS X, various Linuxes, and popular mobile phone platforms, including iPhone, Android, and BlackBerry. Because the KeePass database is stored in a single file, it's easy to distribute among your NOC team. Did I mention that KeePass is portable, needing no installation on Windows or Mac OS X? You can carry it with you on a USB stick or download it to a computer without leaving any unwanted registry entries or library files.
Already using another password manager? KeePass can import your existing password database in formats from a variety of programs such as Password Keeper, CodeWalletPro, and Password Agent. Other file formats are supported through KeePass plug-ins.
Top free open source tools for network admins: IPplan
We network admins must keep track of which IP addresses we have, which are in use, and which are available to be allocated to the systems administrators who always want yet another IP address for their servers. Are you tracking your IP addresses in an Excel spreadsheet? Well, stop! Get the benefits of using a real database with IPplan.
