This article provides information about how to use the Server Configuration wizard to configure network monitoring and how to view network status in the Neverfail Heartbeat Management Client.
The Neverfail Heartbeat Management Client provides you the opportunity to configure network monitoring and view the status of your network. Configuration of network monitoring follows the procedure listed below.
To configure network monitoring, navigate to Start > Programs > Neverfail > Configure Server , and select the Network Monitoring tab.
On the screen are the Public Network Connection pane and the Split-Brain Avoidance pane.
Public Network Connection
The connection between the active server and the principal (public) network can be monitored. It is recommended that you enable this option, which allows the set of addresses to be chosen automatically. This is not enabled by default.
This setting can be used to ensure that only one server becomes active if the channel connection is lost with both servers still connected to the principal (public) network.
This operates by 'pinging' from the passive server to the active server
across the principal (public) network. If the active server responds,
the passive server will not failover, even if the channel connection
is lost. This requires the active and passive servers to have different
IP addresses on the principal (public) network, which is typically the
case for WAN installations.
To enable this test, you will need to enter the principal (public) IP address used by each server.
You will also need to configure auxiliary IP addresses on your principal (public) network cards. This is required in order to allow the passive server to send a 'ping'. Once you have made your changes, click Finish to apply them and close the wizard. Pressing Reset reverts the settings to the last applied values. Both servers can be independently configured by running the wizard and following these instructions.
Enabling Split-Brain Avoidance in LAN environments requires a separate NIC to be installed on each of the Primary and Secondary servers. Neverfail Packet Filter Driver should not be enabled on these two NICs which will allow them to communicate over the network. Neverfail should be configured to use the IP addresses of the additional NICs for the Split-Brain Avoidance.
Auxiliary IP Addresses
These are additional IP addresses assigned to the network cards connected to the principal (public) network. They are used to allow the passive server to communicate on the principal (public) network, because unlike the principal (public) network IP address, they are not filtered.
When configuring Neverfail for use with Microsoft Exchange, it is important
to remember that Microsoft Exchange servers frequently use reverse DNS lookup
for authenticating the origin of email. Since Microsoft Exchange inserts the
first IP address of the sending server into the header of an SMTP packet, reverse
DNS lookup may check against the management IP address, consequently failing
to validate the address and inadvertently marking the email as spam. As a result,
management IP addressing should not be used when Microsoft Exchange is installed.
See Knowledgebase article #491 — Neverfail for Exchange is not supported with WINS registration using management IP addresses in a WAN environment .
The auxiliary IP address is used by the passive server to send 'pings', and is required by the passive server to send email alerts.
To configure an auxiliary IP address:
- Open the network properties for the Principal (Public) network connection, open the TCP/IP properties, and then click Advanced .
- Enter an additional (currently unused) IP address in the table. Reposition the IP addresses in the list so that the additional address appears first, and the Principal (Public) network address, by which clients connect to the server, appears second. You can reposition the IP addresses by removing the top one and adding it again at the bottom.
How to View the Network Status Using the Neverfail Heartbeat Management Client
Launch the Neverfail Heartbeat Management Client, and then
tab to bring
screen. This screen indicates the Principal
(Public) network connection and the split-brain prevention check, if these have
been enabled. The Public Network Connection status is determined by pinging
a selection of hosts on the network. If there is no response, and active server
connections have been compromised, then a switchover is initiated to the other
You can configure Neverfail Heartbeat's behavior by selecting the Configuration tab and changing the settings in the Public Network Connection Check section.
Click Apply to save the changes or click Reset to revert to the last saved settings.