Explanation
Load balancers. These are used to distribute traffic to virtual machines in the application-tier subnet. For high availability, use the built-in SAP Web Dispatcher, Azure Load Balancer, or network appliances, depending on the traffic type (such as HTTP or SAPGUI) or the required network services, such as Secure Sockets Layer (SSL) termination.
Reference:
https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/sap/sap-netweaver

Explanation
You set up alerts on Azure VPN Gateway metrics. Azure Monitor provides the ability to set up alerts for Azure resources. You can set up alerts for virtual network gateways of the "VPN" type.
Metric: AverageBandwidth: Average combined bandwidth utilization of all site-to-site connections on the gateway.
Reference:
https://docs.microsoft.com/bs-latn-ba/azure/vpn-gateway/vpn-gateway-howto-setup-alerts-virtual-network-gatew

Explanation
Check for activity on the VF (virtual function) with the ethtool -S eth0 | grep vf_ command. If you receive output similar to the following sample output, accelerated networking is enabled and working.
vf_rx_packets: 992956
vf_rx_bytes: 2749784180
vf_tx_packets: 2656684
vf_tx_bytes: 1099443970
vf_tx_dropped: 0
Accelerated Networking is now enabled for your VM.
Reference:
https://docs.microsoft.com/en-us/azure/virtual-network/create-vm-accelerated-networking-cli

Explanation

Step 1: Create a virtual network...
We recommended that for test failover, you choose a network that's isolated from the production recovery site network specific in the Compute and Network settings for each VM. By default, when you create an Azure virtual network, it is isolated from other networks. The test network should mimic your production network:
The test network should have same number of subnets as your production network. Subnets should have the same names.
The test network should use the same IP address range.
Step 2: Add a public IP address...
Because Site Recovery does not replicate the cloud witness, we recommend that you deploy the cloud witness in the disaster recovery region.
Step 3: Shut down production virtual machines
Make sure that the primary VM is shut down when you run the test failover. Otherwise there will be two VMs with the same identity, running in the same network at the same time. This can lead to unexpected consequences.
Step 4: Select Test failover from the Recovery Plans blade
References:
https://docs.microsoft.com/en-us/azure/site-recovery/site-recovery-test-failover-to-azure

Explanation
To create a swap file in the directory that's defined by the ResourceDisk.MountPoint parameter, you can update the /etc/waagent.conf file by setting the following three parameters:
ResourceDisk.Format=y
ResourceDisk.EnableSwap=y
ResourceDisk.SwapSizeMB=xx
References:
https://support.microsoft.com/en-us/help/4010058/how-to-add-a-swap-file-in-linux-azure-virtual-machines