Simple Failover
"Simple Failover" is a new software based failover
solution. The concept really is simple; it
continuously monitors your servers to find out which are up and which are down,
and then it dynamically updates your DNS records accordingly so that your domain
name always points to a functional server.DNS records are updated directly via
the DNS protocol (optionally using encrypted signatures for security), via WMI,
via HTTP based dynamic IP updates, or via custom scripting.
It can also send you e-mail notifications when problems are detected, and it can
be extended through scripting to provide custom notifications, logging, and data
capture, and has many other features...
Simple Failover ensures that if your primary
server is ever un-available, your users are automatically directed to a
backup server.
The concept really is quite simple:
Simple Failover continuously monitors your servers to find out which are up
and which are down, and then it dynamically updates your DNS records
accordingly so that your domain name always points to a functional server.
It works with web-servers (HTTP), mail-servers (SMTP, IMAP, POP3),
FTP-servers, and practically any other TCP/IP based server type. |
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Click for full-size screen shots |
DNS records are updated directly via the DNS protocol
(optionally using encrypted signatures for security), via WMI, via HTTP
based dynamic IP updates, or via custom scripting.
Simple Failover can also send you e-mail notifications when problems are
detected, and it can be extended through scripting to provide custom
notifications, logging, and data capture, and has many other
features |
Monitor and failover protect your servers
Simple Failover continuously monitors your servers and updates DNS accordingly,
so that you domain name is always pointing to a functional server.
Web-servers (HTTP) as well as FTP, SMTP, POP3, IMAP, NNTP servers can be
monitored for protocol specific responses, and other server types can be
monitored via TCP connect or Ping.
Flexible DNS update methods
Simple Failover can update DNS servers utilizing 5 different methods:
1) Standard dynamic DNS updates via the DNS protocol.
2) TSIG signed dynamic DNS updates via the DNS protocol (cryptographic
authentication).
3) Via WMI (Windows Management Instrumentation).
4) Via HTTP against HTTP based dynamic IP services.
5) Via scripting.
This means that it works with practically any DNS server running on any
operating system.
Customizable e-mail notification
Simple Failover can send out e-mail notifications whenever a problem is
detected.
A different e-mail recipient address can be defined for each server set
monitored.
The subject and message body of the e-mail notification is user defined.
This can also be used to send pager or SMS message notifications (via
appropriate gateway).
E-mail notification uses a built-in SMTP engine, and therefore does not have to
depend on any local mail system.
Extensible through scripting
Various functions in Simple Failover can be extended through custom
scripting using any scripting language supported by Windows Scripting Host
(VBScript, JScript, Perl, etc.). This makes it possible to define your own
logging procedures, store server availability statistics in a database, send
custom problem notifications, update non-standard DNS servers, etc.
HTTP API interface It is possible to create/update server sets, retrieve status information, and
control most other functions in Simple Failover via HTTP. This opens the
possibility of creating your own web-interface to Simple Failover, and/or
integrating it with your existing hosting solutions. All data is exchanged in
XML format, and the commands and data formats are described in detail in the
documentation.
Configurable polling intervals and DNS TTL values
Simple Failover can be configured to perform the server monitoring at user
defined intervals to match your needs.
DNS records TTL (time to live) values can be configured to control DNS caching.
Support for DNS Round Robin load balancing
Simple Failover can update DNS so that all functional servers for a domain name
receives traffic on a rotating basis (utilizing DNS round robin), or it can
update DNS so that only one server receives traffic (by server priority) if you
have a primary server and one or more backup servers.
Intuitive and simple user interface
The main dialog is divided into three main tabs: Server Set tab, Activity Log
tab, and Problems tab.
The Server Set tab consists of an explorer like list of the defined server sets
on the left and associated details on the right.
The Activity Log tab is a live log of what is currently going on.
The Problem tab lists all current problems detected.
Right-click on server to ping
When a server appears to be down, for many, the first trouble shooting step is
to open a command prompt and ping the server IP address. You can ping an
individual server in Simple Failover simply by right-clicking on it in the
Server Set explorer or in the Problem list, and selecting "Ping" from a popup
menu. The resulting ping dialog gives you instant ping statistics, and continues
pinging the server IP address until you close the dialog.
See what's going on behind the scenes - live
The Simple Failover "Activity Log tab" shows what is currently happening, and
how the program reacts to the monitoring process in real time. Everything
translated into human readable text.
If you are trying to learn how Simple Failover works, this can be a real helper.
Online Problem Knowledge Base
Any problem detected by Simple Failover is listed in the "Problem" tab of the
main dialog.
When you select a problem in this list and click the "Online Problem KB" button,
an Internet browser window is opened to search our online database for
information on this particular problem event.
Run as Windows Service
You can optionally run Simple Failover as a Windows Service so that it continues
protecting your servers without anyone being logged into the computer it is
running on.
Windows Event Log
Events (such as detected servers problems) can be sent to the Windows Event Log.
This makes it possible to take advantage of features (such as notification) of
the Windows Event Log service as well as other tools built to work with this.
Balloon tip notification
Simple Failover can display a balloon tip notification from the system tray
to attract attention to important events - for example when a server is not
responding.
Configuration file in XML-format
Simple Failover uses one configuration file "sfo.config.xml" to store all
the programs options and server sets definitions.
This makes it easy to interface with Simple Failover from other software etc.
Flexible support system
The help menu / Support file function generates a text file with extended
support information for precise and personal diagnostics by the support staff.
Comprehensive documentation
The user manual, available both as a standard help file and a
pdf versio, contains thorough explanations of both general concepts and
individual configuration options.
Several sample scenarios and walkthroughs are also included.
You can also get specific help for any data entry fields in the software simply
by pressing the F1 key.
RFC's supported
RFC821 SMTP Simple Mail Transfer Protocol
RFC959 FTP File Transfer Protocol
RFC977 NNTP Network News Transfer Protocol
RFC1035 Domain names - implementation and specification
RFC1939 POP3 Post Office Protocol – Version 3
RFC1945 HTTP Hypertext Transfer Protocol - HTTP/1.0
RFC2136 DNS Update Dynamic Updates in the Domain Name System (DNS UPDATE)
RFC2845 TSIG Secret Key Transaction Authentication for DNS (TSIG)
RFC3501 IMAP Internet Message Access Protocol - Version 4rev1
Standard vs Professional license comparison
| Feature |
Professional
license |
Standard
license |
| Monitor HTTP, FTP, SMTP,
POP3, NNTP, and IMAP servers |
 |
 |
| Monitor any TCP based
server type (generic TCP connect) |
 |
|
| Monitor servers using PING
(ICMP Echo) |
 |
|
| Max. number of Server Sets*
monitored |
unlimited |
5 |
| Max. number of individual
servers in a Server Set* |
unlimited |
2 |
| Max. number of DNS alias
domain names per Server Set* |
unlimited |
1 |
| Max. number of DNS servers
updated per Server Set* |
unlimited |
2 |
| Update DNS records on all
major DNS server platforms |
 |
 |
| Customizeable e-mail
notification |
 |
 |
| Extensible through
scripting |
 |
 |
| Configurable polling
intervals and DNS TTL values |
 |
 |
| Support for DNS Round Robin
load balancing |
 |
 |
| Online Problem Knowledge
Base |
 |
 |
| Run as Windows Service |
 |
 |
| Windows Event Log |
 |
 |
| Balloon tip notification |
 |
 |
| Configuration file in
XML-format |
 |
 |
| Comprehensive documentation |
 |
 |
| Right-click on server to
ping |
 |
 |
| Monitor service protocols
on non-standard port numbers |
 |
 |
| Configurable server
response status codes |
 |
 |
| HTTP API interface |
 |
|
| * A "Server Set" represents one
or more physical server computers hosting the same single service (such as
one web-site) for the same domain name (such as "www.yourname.com"). Each
unique service represents another "Server Set", also when these are hosted
on the same physical server computers. |
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