Symptoms:
The NSX Load Balancer, by default, will use layer 7 for the virtual servers that are created. For better performance, we may use "Enable Acceleration" for the virtual server, which means the Virtual Server will be converted to Layer 4 load balancing.
To perform this change without causing a system outage, ensure there are no settings that will force the engine into Layer 7 mode. if there are L7 settings, such as http cookie persistence, url algorithm, ssl termination etc, LB will use L7 engine only. For more information, see SOL-6421.
In the case of other Layer 7 Virtual Server on the Load Balancer,:
The existing connections will stay active and continue to work.
NOTE: existing Layer 7 connections will not longer display in the "show service loadbalancer session
" command after acceleration is enabled but the connections will continue to run normally. When the connections reset normally, they will reconnect on the Layer 4 engine and will show up in the "show service loadbalancer session
" command. Having both a Layer 7 Virtual Server and a Layer 4 Virtual Server running will result in two haproxy engines to be running. This can be confirmed by running 'show process list
' on the load balancer and finding two haproxy processes.
Example:
edge> show process list
0.0 0.0 20508 712 Ss+ 09:51:49 00:00:00 /sbin/agetty --noclear tty1 9600
91.0 0.1 22880 1440 Rs 10:16:26 00:05:58 /usr/local/sbin/haproxy -f /var/db/vmware/vshield/haproxy.conf -p /var/run/haproxy/haproxy.pid -D -L lb-0 -sf 23663
0.0 0.1 22856 1260 Ss 10:22:26 00:00:00 /usr/local/sbin/haproxy -f /var/db/vmware/vshield/haproxy.conf -p /var/run/haproxy/haproxy.pid -D -L lb-0 -sf 24290
If no other Layer 7 Virtual Server on the Load Balancer: All the existing connections will be dropped and new connections will be established on the new Layer 4 engine. This occurs because the Layer 7 engine is stopped and the Layer 4 engine is started.
To work around the issue when there is no other Layer 7 Virtual Server on the load balancer:
show process list
" and verify there are two haproxy processes (engines).show process list
" will show only one haproxy processNOTE: existing Layer 7 connections will not longer display in the "show service loadbalancer session
" command after acceleration is enabled but the connections will continue to run normally. When the connections reset normally, they will reconnect on the Layer 4 engine and will show up in the "show service loadbalancer session
" command.