The cause of this issue is due to certain network settings of some network adapters which affect the network emulation.
To fix this issue:
LR/PC 12.50 / 12.53- On each Load Generator / NV Test Manager:
1. Open Windows Control Panel.
2. Select Network and Sharing and then Change adapter settings.
3. Open the properties of the adapter/s through which the
application under test communicates
> select Configure > Advanced:
* Large Send Offload (IPv4) > Disable.
* Recv Segment Coalescing (IPv4), if the option exists > Disable.
LR/PC 12.53 Patch 4 / 12.55- On each Load Generator / NV Test Manager
1. Open Windows Control Panel.
2. Select Network and Sharing and then Change adapter settings.
3. Open the properties of the adapter/s through which the application under test communicates > select Configure > Advanced:
* Recv Segment Coalescing (IPv4), if the option exists > Disable.