We’ve now made it really easy for companies that offer web hosting and server hosting services to be able to resell server monitoring services to their customers.

The first phase of our reseller program is aimed at users of popular hosting billing software platforms ‘HostBill‘ and ‘WHMCS‘.

So how does it work?

Step 1. You will need your own Sentinel Server Monitoring account. To get this just head on over to sentinelmonitoring.com and sign up on our free 1 month trial.

Step 2. Once you have had a look around and seen how easy Sentinel server monitoring is to use and all the things that it can monitor – you can upgrade your account off the trial and onto a full featured Sentinel server monitoring account.

Now – We realise that some of you will want to try out the reseller part of Sentinel without having to pay anything. That’s fair enough. Unfortunately, the reseller portion can only be activated when an account has been upgraded. So you will have to put in a valid credit card number and upgrade the account. But here’s the deal. If you email us BEFORE you upgrade your account we can put some credit on there for you so you can make sure that the reseller options work for totally risk free.

Step 3 - Install the appropriate module into WHMCS or HostBill.  (You will need to be logged into Sentinel to download these modules)

• Hostbill Module – Download here
• WHMCS Module – Download here

Step 4 – We’ve put together a bunch of videos that show you how to set up the Sentinel Server Monitoring module inside HostBill or WHMCS. Have a look at the HostBill videos here .. and the WHMCS videos here.

That’s it! – You’re pretty much all done now.
We recommend that you take a look over our Reseller help article, this details the base costs for the reseller program, as well as the specific help article for HostBill and the specific help article for WHMCS

Sentinel server monitoring now has a really simple interface to allow you to set periods of scheduled downtime for any server that you monitor.

While your server is in a period of downtime we’ll continue to monitor it but we wont send alerts for any problems that we detect. Scheduled downtime does not count towards your server availability detailed in your weekly report.

Click through the gallery below to see the process for setting Scheduled Downtime with Sentinel.

We have just added a new checking node into our ever growing global server monitoring network.

The new node is at: 176.58.90.240 and is based in Paris, France.

UPDATE: Our API is now live. Check out the documentation here.

A little while ago we launched a very simple API for Sentinel which we called ‘version 1′. Check out this example here on how we used it create a basic integration with Zendesk.

Well, over the last 6 weeks or so, Tim has been working away on creating a fully fledged API (‘version 2′) that will allow third parties to do pretty much whatever they need to with Sentinel from within their own systems.

So far we have full support for adding and removing servers, adding and removing services (checks) as well as the ability to add and remove contacts on your account and much more to come.

Tim has also been documenting everything so, before we release our brand spanking new website (that’s still a few weeks away), we’ll get the API documentation out as a public facing page so that you can all get busy with it.

All going well we will be releasing the API in about a week.

We have just added a new checking node into our ever growing server monitoring network.

The new node is at: 209.177.145.225 and is based in New York, United States.

People ask us this all the time, and while we put our new website together, we thought it would be a good idea to breakdown all the things that Sentinel can keep tabs on for you. So grab a coffee & stay focused because it’s a big old list.

With Sentinel you can monitor a wide variety of services both external (HTTP, POP3, SMTP etc) and internal to your server (DISK, MEMORY etc).

All of these services can be monitored at time intervals right up to every minute and alerts can be delivered via any combination of SMS, Email, Twitter DM, iPhone Push (via Prowl) and our API.

Every service that you monitor with Sentinel have base settings that include;

• Friendly name – A way to give the service a more meaningful name. Very useful if you have multiple instances of a service on the same server.
• Confirmation checks – The maximum number of times for Sentinel to check a server or service to confirm the problem exists, before sending out an alert.
• Confirmation retry interval – The number of minutes to wait between confirmation checks.
• Reminder interval – The duration to wait after we send the first alert, before reminding you again about the problem.
• Flap Detection – The formula we use to determine if a service is rapidly changing between OK and non-OK states. Can be disabled it not required.

Below is a comprehensive list of all the services that the Sentinel Server and Website Monitoring system can currently monitor.

External services

These are services that are exposed to the Internet. Each have default options and some have additional parameters that you can specify too. These services are able to be monitored on any server operating system.

PING

PING is the default service that we add every time you add a server to monitor on Sentinel (by default Sentinel will PING your server every 5 minutes). The PING check can be disabled at anytime as long as there is another check type in place for that server.

Options for the PING check:

• Warning settings for Latency & Packet loss – When this threshold is reached Sentinel will send out a WARNING alert.
• Critical settings for Latency & Packet Loss – When this threshold is reached Sentinel will send out a CRITICAL alert.
• Packets – Number of PING packets to send.

HTTP

HTTP is the standard check we use to monitor a website. It has quite a few options and good to know that you can have MULTIPLE HTTP checks per server if you want to. This is very good if you have multiple pages (or HTTP servers) on your server that you wish to monitor.

Options for the HTTP check:

• Uri – The web page that you want to check. The default setting is “/” but you can check any page that you like.. eg /shopping-cart/ or /sign-up.php. This is quite useful to ensure that critical web pages on your site are actually there and haven’t been removed or replaced with a generic ‘Your site has been hacked’ page.
• Vhost – The (virtual) host name you wish to check (default is the server name). You can monitor as many virtual hosts as you like on each server.
• Port – The network port number to check (default is port 80).
• Warning Latency – The number of seconds it takes to get a response before sending a warning alert. Disabled by default.
• Critical Latency – The number of seconds it takes to get a response before sending a critical alert. Disabled by default.

HTTPS

HTTPS is the standard check we use to monitor secure HTTP websites.

HTTPS options include:

• Port – Set to 443 by default but you can change that if you like.
• Uri – Works the same way as the Uri for the HTTP check.

SMTP

SMTP is the check that we use to make sure that your incoming mail server is available.

The only option currently configurable for SMTP is the Port (set at 25 by default).

IMAP

If you run an IMAP server or just need to check that mail is available for your customers then this is the check for you.

The options you can change on this are:

• Port – Set to 143 by default.
• Username – If you specify a username and a password then Sentinel can test that your IMAP server is actually authenticating accounts.
• Encryption – You can tell Sentinel whether or not to use encryption to connect to your IMAP server. Options here are, None (default), SSL and TLS.

POP3

If you run a POP3 server or just need to check that mail is available for your customers then this is the check for you. The options are the same as the IMAP server above in that you can specify the following…

• Port – Set to 110 by default.
• Username – If you specify a username and a password then Sentinel can test that your IMAP server is actually authenticating accounts.
• Encryption – You can tell Sentinel whether or not to use encryption to connect to your IMAP server. Options here are, None (default), SSL and TLS.

CERTIFICATE

CERTIFICATE is an interesting check but surprisingly handy. What it does is simply remind you BEFORE your SSL certificates expire. Very handy indeed! The certificate check frequency is set to ‘Every day’ by default (rather than ‘Every 5 minutes’ for all the other services). This check allows you to check for HTTPS, POP3 and IMAP secure certificate expiry to ensure your clients applications don’t get met with nasty error messages!

Options include:

• Type – Choose either HTTPS, POP3S, or IMAPS.
• Warning – The number of days before expiry to send out a WARNING alert.
• Critical – The number of days before expiry to send out a CRITICAL alert.

DNS

With Sentinel you can check that the DNS service is running and able to return the DNS entry for a given domain name.

Options include:

• Host – The domain name to check for on your DNS server.
• Timeout – The number of seconds to wait before the check times out. (10 by default).

FTP

Sentinel can check that your FTP service is available. At the moment we don’t support authentication checking for FTP and the only setting that you can change is the Port (21 by default).

SSH

Sentinel can monitor Secure Shell to check that it is available on your server.

Options include:

• Port – The default port is 22.

STREAM (Icecast & SHOUTCast for monitoring streaming radio)

Developed from a customer request, this is perfect if you run an Internet radio station or other streaming audio system. You can monitor MULTIPLE STREAMS on the one server.

Options include:

• Type – Either Icecast or SHOUTCast
• Uri – The stream location. By default this is “/”
• Port – The port that the stream is running over. By default this is 80.

TCP (generic service)

Sentinel allows you to monitor the transport layer over any port you like.

Services that run on your Server

By installing a small piece of software on your servers (the Sentinel AGENT software) you can then use Sentinel to monitor and alert you about physical properties and services running on your servers.

The Sentinel AGENT runs on most current Linux Distributions, Mac OS X 10.5+ and Windows operating systems. Below is a table of the services that we can monitor on each of these operating systems.

DISK SPACE

Sentinel can check the available disk space on any partition on your server and it can send you a WARNING alert when you have a certain percentage (or megabytes) of free disk space remaining and a CRITICAL alert when you have a certain percentage of free disk space remaining.

Options include:

• Partition (or Disk) to check – By default this is “/”
• Warning – The warning %, or megabyte amount of free space remaining (Default is 20%)
• Critical – The critical %, or megabyte amount of free space remaining (default is 10%)

LOAD

Sentinel can check the LOAD on your servers and alert you when WARNING and CRITICAL thresholds have been reached.

Options include:

• Warning Threshold – The warning load level for 1min, 5min and 15min averages
• Critical Threshold – The critical load level for 1min, 5min and 15 min averages

PROCESSES

PROCS is very useful to ensure that certain processes are running on your server. A classic example would be to use the PROCS check to make sure MySQL or CRON was running on your server.

Options include:

• Process – The name of the process on the server. eg: myslqd
• Range – The range of processes to be considered OK (defaults to 1:65535) eg: 1:10 would alert you if there is LESS than 1 process running or MORE then 10 processes running

SWAP SPACE

Sentinel can tell you if your swap space drops below a certain percentage (indicating that memory is getting dumped to swap). The default percentages are to send a WARNING alert if swap drops below 90% and a CRITICAL alert if swap drops below 80%.

MEMORY

Sentinel can monitor MEMORY usage on Windows servers and alert you when certain thresholds are reached.

MAIL QUEUE

Sentinel can check the amount of Mail in the queue for various common Mail applications and you can specify WARNING and CRITICAL thresholds to send alerts.

Options include:

• MTA – Mail Transfer Agent can be either Postfix, Sendmail, Exim or QMAIL.
• Warning – Warn if there are more than x number of messages in the mail queue.
• Critical – Warn if there are more than x number of messages in the mail queue.

NTP – Network Time Protocol

We can check your server clock against a NTP host server to ensure that your system clock is nice and accurate.

Options include:

• Hostname – The host name of the NTP server you wish to check your clock against.
• Warning – The number of offset seconds that should be considered a warning (defaults to 0.5).
• Critical – The number of offset seconds that should be considered critical (defaults to 1).

We have just added a new checking node into our ever growing server monitoring network.

The new node is at: 202.174.176.229 and is based in Sydney, Australia. That will keep things nice and fast for our friends across the ditch.

We have set up a new checking node in Amsterdam, Netherlands and should help make confirmation checks from Sentinel monitoring even more accurate of those of you in Europe.

We have an Australian node coming online soon, stay tuned.

As you may know the number of IP addresses are coming to an end (well all on the Internet as “we know it”) and as such there is demand to push more and more services and devices onto the Internet using IPv6 IP addresses. IPv6 IP addressing is somewhat different and, as such, requires a bit of trickery to make some existing systems work with it – hence the hesitation in transitioning to the Internet via IPv6.

At Sentinel we want to make sure you can monitor your servers anywhere (IPv4 or IPv6) and keep the experience as simple as possible so we’ve integrated IPV6 monitoring directly into our dashboard and it works just like ‘normal’ (IPV4).

For the techo’s out there you might be interested to know that due to the adoption of IPv6 we have used a technique called “dual stack” to allow our monitoring nodes to be connected to the Internet via both IPV4 and IPv6.

A number of the providers we host our checking  nodes with don’t currently provide “native” IPv6 connectivity to us and as such we are very thankful for Hurricane Electric’s tunnelbroker service. That allows us to connect to the Internet via IPv6 using their sweet system. Keep up the good work there guys!

We are really excited about this milestone, a quick Google shows there are less than a handful of companies providing monitoring of servers and devices on the Internet via IPv6.

A few years ago, Tim and I (along with a couple of other friends) started one of New Zealand’s most successful web hosting companies – iSERVE limited. iSERVE grew quickly and, as a result of that growth, one of the major headaches we faced  was that we rapidly out grew our accounting system.

We were using MYOB and, despite reassurances, it just didn’t scale and there was no easy way to interface with it. In fact, I believe that Tim and Brent actually ended up hacking it apart so that we could get it to perform what we needed it to. That allowed us to interface with it .. sort of .. but it still wouldn’t scale. Enterprise solutions were well out of our budget then and we were stuck having to do a lot of manual work to make things tick along.

Fast forward a few years, iSERVE has been and gone (absorbed by the fine folk at Orcon internet), but one of the key lessons we took from running that business was to make sure that all our supporting systems were as streamlined as possible. By supporting systems I’m referring to communication systems, help desk systems, accounting systems etc. The systems you need to help your core business run smoothly. You see, at iSERVE, we tried to develop virtually all of those supporting services ourselves and we spent so much time developing them that we neglected our core business system … the piece that our customers used.

When we started developing Sentinel Server & Website Monitoring we were damn sure that we wouldn’t make that mistake again … and, when it came time to sort out our accounting system, Xero.com was a no brainer.

So how does Sentinel use Xero?

We use Xero in two ways.

1. We use it as our general company accounting system.
Xero is hooked into our bank feed and we can get a live update of whats going on at anytime of the day or night and with a few clicks of the mouse we know how much money to put aside for the tax man.This means that Tim and I, and anyone else that we invite along, can get a real time view of our financial position. Something that was very difficult to do with iSERVE.

2. We interface directly with the Xero API from inside the Sentinel Server Monitoring dashboard.
Every invoice that is raised by Sentinel for our customers is automatically handled by Xero. This means that every time a customer decides that they will upgrade their account from the free trial, they enter their credit card details, we process the transaction and raise the invoice in Xero using the Xero API. The next day, when our bank deposits the money into our account, we can log into Xero and with the click of a button, reconcile the transaction against the invoice and everything is squared up.

Aside from being a fabulous accounting system, Xero.com is a true Kiwi success story. The company seems to go from strength to strength, their product is well thought out, well presented and well supported. It is also very affordable with simple monthly payments. That fact alone was great for us as it meant we had very minimal start up costs and could get things up and running very very quickly.

Software as a Service

Xero, Zen Desk, Campaign Monitor and Sentinel Monitoring all represent a shift in the way that we consume software. We are rapidly moving from a model where you buy the software once and then pay for upgrades every couple of years to a model where you pay a small monthly fee and get upgrades (and a host of other benefits) continually. This model is often referred to as ‘Software as a Service’ (SAAS) and it is something that both Tim and I love.

At Sentinel, we use other great SAAS products like Zen Desk and Campaign monitor to help us run our business. We also use Google Docs and Echosign to flash out agreements and get them signed. I’ll elaborate on how we use these products in upcoming blog posts but in the mean time I’d love to hear what SAAS products you use to help run your business! Leave a comment below or, if you prefer, leave a comment on our facebook post.