There is a cool Firefox extension available called Mr. Uptime. With it you can monitor sites that are currently not available, and it will notify you when the site is back up and running. I’m guessing that this is going to appeal the most to the Digg crowd since they constantly encounter sites that collapse under heavy load.
How does it work? A toolbar will appear anytime that you get "Page Not Found" message, and from that toolbar you can begin monitoring the site to see if it is back up yet. There is also a right-click menu option that will let you highlight text and watch for that text to change on the page. This would be useful for a site that is performing maintenance where there is no error, but you can still have Mr. Uptime monitor for when the text changes.
Here’s a list of it’s features:
- Status change – Watch when the server status code changes from an error to OK (HTTP status code 200).
- Regular Checks – Mr. Uptime checks for updates every 5 minutes for the first 60 minutes. Every 10 minutes for the next 120 minutes. Every 15 minutes for the next 180 minutes. Every 30 minutes for the next 240 minutes. Every 60 minutes after that.
- Efficient – It uses less bandwidth than a regular visit to a website since it either just checks the web server response or if a string exists or not on the page. It doesn’t load any images, etc.
- Keywords – Set a keyword that the website should or should not contain to be considered ok.
- Time to watch – Set how long you want to keep checking a website. After this time it will be removed from the watchlist even if it hasn’t become available.
- Notifications – Choose to open the website in a new tab or a new window when it becomes available. You can also optionally get an alert dialog box to notify you when a website is working again.
- Easy to use and discreet – The interface will not clutter your Firefox window. The toolbar is only shown when an error is encountered or when you choose to open it yourself. You will not get another toolbar taking up valuable space in Firefox.
This isn’t an extension that I’m going to install simply because I don’t come across enough sites that are down on a daily basis. I maybe come across two or three each week, so this would be pretty unnecessary for me. If downtime is a frequent problem for the sites you visit, or they are constantly undergoing maintenance then this would probably be pretty useful.