Six Free Tools Every Sysadmin Needs
The following is a blog from Sys-Con Media, written by Hovhannes Avoyan.
"Everyone likes freebies, especially sysadmins. We’ve offered free services longer than premium ones. Monitor.us, our free website monitor, has been up for about 5 years now. This post will cover six free and useful web tools that Monitis offers for every website and systems administrator.
1. Monitor.us is a free monitoring service that checks the availability and performance of websites and servers. Users can enter all their website URL’s, monitor them from global locations, and receive reports and alert notifications when a URL goes down. Unlike other free monitors, Monitor.us also offers free internal monitoring, so users can check the CPU, Memory and Disk utilization on their servers, among other metrics. This recent post shows how to set up free internal monitoring in Monitor.us. All free monitoring is done at 30 minute intervals and users can upgrade to Monitis for 1-minute intervals. We recently changed the domain name to monitor.us from mon.itor.us, but both URL’s till take you to the free service.
3. Instant Ping
This free TCP ping service allows web administrators to perform instant availability checks from multiple locations. It also allows users to embed the ping component into their blog or site. One of the most useful and reliable network debugging tools, the remote ping can be used to perform several Internet network diagnostic tests: to see if a user can reach a public server, to determine how long it takes to bounce a packet off of another site, and to probe either a domain name or an IP address. It is the best way to uncover network problems.
4. Visual Traceroute: Monitis Global Traceroute, which will be available to all visitors of the Monitis website (http://traceroute.monitis.com), is a network diagnostic tool that is used to determine the “path” and transit times that packets take from one IP address to another, simultaneously from multiple global locations up to user servers. Traceroute tools are often used for network troubleshooting. Monitis Global Traceroute can help identify routing issues or misconfigured firewalls that may be blocking ICMP/ping signals to a site. Monitis Global Traceroute can also be used by penetration testers to research network infrastructure and IP ranges around a given host. In case of multiple mirroring servers, system administrators can trace each mirror to determine which is faster for each location.
5. The IP Subnet Calculator helps the network administrator to find the Wildcard Mask, Broadcast address, Subnet ID, Hex IP, Subnet Bitmap and host address range. The user enters the IP address, Subnet Mask, Network class, Mask Bits, Hosts per Subnet and maximum Subnets and the result is shown within seconds. The network and subnet parts are separated from the host address that results in Network address and host identifier. More at: http://portal.monitis.com/web/guest/subnet-calculator.
6. The Wildcard Mask calculator calculates First address and Last address. It is inverted form of subnet mask and is used as an extension of IP address. This calculator can be used in simple Access Control List (ACL) wildcard mask calculations. The Wild Card Mask allows passage to data from the IP address and its associated mask range. The user just has to enter the IP address and select the Wildcard Mask. More at: http://portal.monitis.com/web/guest/network-wildcard"
A good article by Mr. Avoyan.