Specify network interface for redundancy

[acrestar]

Hello!

Would it be possible to specify in the config file one specific network interface for stablishing communication between peers in a redundant system?

Something like when specifying the port in the data or event entries or specific configuration entry?

For example:

Code: Select all

useNetworkIface="ethXXX"

Best regards,
Adrian

[leoknipp]

Hello,

there is no possibility to define a network adapter by name which shall be used for the communication. Which network adapter is used is defined by the network and project configuration.

Normally in redundant WinCC OA system you also have redundant network connection.
The server definition is made with the data = "..." and event = "..." entries including the hostnames or IP-addresses for the redundant connections.

For details please have a look at the WinCC OA online help: Special functions --> Redundant network connections

Best Regards
Leopold Knipp
Senior Support Specialist

[Gertjan van Schijndel]

You could try the 'localAddress' config entry in the data and event config sections to specify the bind address.

[acrestar]

Thanks Leopold,
this worked like a charm.

The only thing that I don't have clear is regarding the interfaces IPs.
Instead of using a specific IP, would it be possible to use DHCP and then let the DNS translate the IP into the appropiate hostname?

Best regards,
Adrian

PS: Also thanks to Gertjan. I didn't know about the localAddress keyword.

[fmulder]

In our configuration we use 2 simple cross-cables between the two redundant servers.

* This allows for the highest possible network speed
* It is cheap but very reliable
* It takes away the synchronisation or recovery network traffic from your 'normal' network

The cross-cables is a simple but effective solution to increase the performance, quality and availability of the network between the servers.

Good luck

[leoknipp]

Hello,

in a WinCC OA system it is recommended to define the IP-addresses and hostnames in the hosts-file of the operating system (see the mentioned chapter in the WinCC OA online help).
Resolving the IP addresses can be a problem if the DNS server cannot be reached. Some tasks in WinCC OA will be delayed then when the WinCC OA process is sending the request to the operating system to resolve the IP-addresses/hostnames.
How long it takes until the system is sending the answer for resolving the names is part of the operating system and cannot be changed within WinCC OA. It can take up to several seconds which is blocking some other tasks in WinCC OA then.

Best Regards
Leopold Knipp
Senior Support Specialist

[acrestar]

Hi!

Thanks a lot for the explanation. We will stick with fixed IPs then.

Best regards,
Adrian