I wrote a plugin for Munin to ping every five minutes websites I have to manage.
You can :
- manage several sites in separated graphs or on the same one
- manage http and https servers with wrong certificates websites
- test website with
- a match keyword in the source
- an exact size in bytes of the source
- a size in bytes of the source greater than a target size
- a size in bytes of the source lower than a target size
- set a custom timeout value
- receive a warning alert for slow connections
- receive a critical alert for down website connection
More informations here.