How does Vigil's monitoring work?

When you add a site to monitor to Vigil, it is sent to our backend monitoring server. Depending on your plan, the backend server will attempt to contact the site either every minute, two minutes, five minutes or ten minutes, recording the amount of time it took for the site to respond. If the site fails to respond, or returns with an error (normally any status code other than 200), the Vigil server will run a second request against the server. If this second request also fails, the Vigil server will send out a push notification letting you know that something is wrong with your site.

What do these status codes mean?

The HTTP protocol defines a number of Status Codes that a server can return in order to let a client know whether a request was successful or not. Even though a server may be responding, the data it may be returning could indicate something is wrong. Here are some common status codes you might see:

2xx - 200 is the most common status code, and indicates a successful response. Any status code in the 200-range is considered a success. Additional status codes you might see are 201, 202, 203, 204, 205 and 206.

206 - You will often see a 206 status code from the Vigil monitors. In order to save bandwidth we only ask for a partial download of your site—typically 200 bytes. The response code when you ask for only a portion of the data is 206.

3xx - Status codes in the 300 range indicate a redirect, and means the client must do additional work to fulfill the request. Normally, the Vigil server will follow these redirects on its own, and you will not see these status codes. Possible values are 300, 301, 302, 303, 304, 305 and 307.

4xx - Status codes in the 400 range indicates the server thinks the client, in this case the Vigil server, made some kind of error. The most common error of this type is the 404, or Not Found error. This usually means a URL has been typed incorrectly. It can also mean a resource has moved on the server, and is no longer at the original URL. Another error you might see is 401, or Unauthorized. If your site requires credentials to access the resource requesting, you might see this error. Error codes in the 400 range are 400, 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416 and 417.

5xx - Status codes in the 500 range indicate an error on the target server itself. These usually indicate something is wrong with a site. 500, or Internal Server Error is a common error when a backend service has failed. Additional codes are 501, 502, 503, 504, and 505.

What does the last check warning mean?

All responses from the Vigil server include a timestamp indicating when the target website was checked. If for some reason the Vigil server has been unable to check a website for an extended period of time, we display a warning indicator. This does not mean the website is down. It merely indicates the Vigil server itself has failed to check the site. This condition will typically resolve itself. We show the warning indicator when it has been more than three minutes since a website has been checked.

What does ping do?

The PING button at the bottom of the detail screen allows you to check on a website from the phone itself. Normally, all checks are performed on our server. However, if you are unable to reach the server for some reason, your subscription has expired, or simply want the comfort of an immediate response, you can hit the ping button, and we will send a request from the phone itself. This response is not included in the history graph.

How do I monitor a secure site?

We normally do not require the http:// portion of a URL when typing it in. In order to monitor a site that requires SSL, simply include https:// at the beginning of your URL.

What does the sensitivity setting do?

The sensitivity setting controls how many failed connection attempts it takes before Vigil considers a site down, as well as how many successful checks it requires before it then considers it back up. Most sites and hosting providers experience some intermittent networking issues which can cause false alerts, even though a site may still be up. We recommend users use the normal setting.

  • Vigilant Vigil will send a down alert after a single failed connection attempt, and will only send out an up notification after five successful checks.
  • Normal Vigil will send a down alert after three failed checks in a row, and will send out an up notification after one successful check.
  • Relaxed Vigil will look for 5 failures in a row before sending out a down alert, and will report a site as up after a single successful check.
  • Off We will not send a push notification when a site goes down or up.

 

What does the 'Ignore SSL Errors' option do?

As part of our site check, we validate the SSL certificate for secure sites. If your certificate is expired, or self-signed, we report it as an error. Setting this option ON will cause us to ignore these types of errors.

What URL format do you accept?

We accept the standard options in a URL string: protocol://username:password@hostname:port/path?query#fragment where the different sections are:

  • protocol Currently we support http and https
  • username:password You can provide a basic-auth username and password, and we will use that to log into the server when connecting. We highly recommend you only use this with the 
    https
    protocol, and use a custom username and password combination you create just for the Vigil monitoring service. Because we need to send this password to your server, we must store it on our server.
  • hostname We support any valid domain name
  • port You can provide a custom port we will use to connect to your server. http defaults to port 80, and https to port 443.
  • path This should be a series of directories separated by /
  • query A standard query string of the format key=value;key=value.
  • fragment You can include a fragment on your url with the # character.

What do the different backgrounds on the graph mean?

If you tap on the bar graph in the LATEST VALUES box and scrub back and forth, it will highlight each section, with a description of each phase of the download. In general order they are: DNS Lookup, Establish a Connection, Negotiate the Connection (usually only noticeable if there is an SSL handshake involved), Time to First Byte and finally Transfer Data.

Will Vigil monitoring show up in my Google Analytics?

Vigil checks should not show up in your Google Analytics data. When Vigil makes a request to your server, it does not execute any JavaScript embedded in the page. Vigil will show up in any local logs your server keeps. You can identify Vigil requests through the Agent String. You can read more about this at our Bot Page