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Alternate Source Address needed on Virtual Service for back end connection





Virtual Service not working due to wrong back-end source IP


Product: LoadMaster

Version: Any

Platform: Any

Application: Any

Question/Problem Description:

Unable to connect to any service because the server will only accept connections from a specific subnet/IP.

Steps to Reproduce:  
Error Message:  
Defect Number:  
Enhancement Number:  
  • Packet captures showed successful front end communication, but the back-end communication would fail after the initial SYN from the loadmaster over port 443, with a flood of Re-Transmissions.
  • Back-end azure environment/servers will only accept connections sourced from a specific subnet range/IP addresses.
  • To fix this, we need to enable the ability to specify an alternate source address.
  • This is located in System Configuration -> Miscellaneous Options -> L7 Configuration -> Allow connection scaling over 64K Connections.

  • Next, you will have to navigate to the Virtual Service that you want to change the Source IP Address of. Navigate to advanced properties -> Alternate Source Addresses and type in the new Source IP Address. You will not need to add the CIDR here.

  • Connections to the virtual service should now work.

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