Fix IPVS persistence flag

[bzub]

Fixes #159

[bzub]

Testing Steps

e2e

passed

custom tests

Create service + http endpoints

kubectl run ipvs --command --image alpine --replicas 10 --expose --port 80 -- httpd -fv

Log snippets:

kube-router-6cs68:kube-router I0914 02:05:51.791244       1 network_services_controller.go:203] Received service update from watch API
kube-router-6cs68:kube-router I0914 02:05:51.791789       1 network_services_controller.go:796] Successfully added service: TCP:10.3.0.42:80 (Flags: )
kube-router-6cs68:kube-router I0914 02:05:51.791806       1 network_services_controller.go:313] Cleaning up if any, old ipvs service and servers which are no longer needed
kube-router-6cs68:kube-router I0914 02:05:51.791917       1 network_services_controller.go:361] IPVS servers and services are synced to desired state!!
kube-router-6cs68:kube-router I0914 02:05:51.791925       1 network_services_controller.go:225] sync ipvs servers took 637.532µs
kube-router-6cs68:kube-router I0914 02:05:52.169283       1 network_services_controller.go:181] Received endpoints update from watch API
kube-router-6cs68:kube-router I0914 02:05:52.169321       1 network_services_controller.go:193] Skipping ipvs server sync on endpoints update because nothing changed
kube-router-6cs68:kube-router I0914 02:05:52.260199       1 network_services_controller.go:181] Received endpoints update from watch API
kube-router-6cs68:kube-router I0914 02:05:52.260383       1 network_services_controller.go:193] Skipping ipvs server sync on endpoints update because nothing changed
kube-router-6cs68:kube-router I0914 02:05:56.892266       1 network_services_controller.go:181] Received endpoints update from watch API
kube-router-6cs68:kube-router I0914 02:05:56.893047       1 network_services_controller.go:804] Successfully added destination 10.2.1.22:80 (Weight: 1) to the service TCP:10.3.0.42:80 (Flags: [hashed entry])
kube-router-6cs68:kube-router I0914 02:05:56.893071       1 network_services_controller.go:313] Cleaning up if any, old ipvs service and servers which are no longer needed
kube-router-6cs68:kube-router I0914 02:05:56.893289       1 network_services_controller.go:361] IPVS servers and services are synced to desired state!!
kube-router-6cs68:kube-router I0914 02:05:56.893304       1 network_services_controller.go:225] sync ipvs servers took 982.897µs

Edited ipvs service with ClientIP session affinity

Log snippets:

kube-router-6cs68:kube-router I0914 02:06:38.113296       1 network_services_controller.go:203] Received service update from watch API
kube-router-6cs68:kube-router I0914 02:06:38.113712       1 network_services_controller.go:771] Updated persistence/session-affinity for service: TCP:10.3.0.42:80 (Flags: [persistent port][hashed entry])
kube-router-6cs68:kube-router I0914 02:06:38.114061       1 network_services_controller.go:313] Cleaning up if any, old ipvs service and servers which are no longer needed
kube-router-6cs68:kube-router I0914 02:06:38.114261       1 network_services_controller.go:361] IPVS servers and services are synced to desired state!!
kube-router-6cs68:kube-router I0914 02:06:38.114273       1 network_services_controller.go:225] sync ipvs servers took 898.11µs

ipvsadm status:

for i in $(kk get pods -l k8s-app=kube-router --output name)
do
kk exec $(basename ${i}) -- ipvsadm -ln
done
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.3.0.1:443 rr persistent 10800
  -> 172.17.4.101:443             Masq    1      0          0         
TCP  10.3.0.10:53 rr
  -> 10.2.0.3:53                  Masq    1      0          0         
TCP  10.3.0.42:80 rr persistent 10800
  -> 10.2.1.22:80                 Masq    1      0          0         
  -> 10.2.1.23:80                 Masq    1      0          0         
  -> 10.2.1.24:80                 Masq    1      0          0         
  -> 10.2.1.25:80                 Masq    1      0          0         
  -> 10.2.1.26:80                 Masq    1      0          0         
  -> 10.2.1.27:80                 Masq    1      0          0         
  -> 10.2.1.28:80                 Masq    1      0          0         
  -> 10.2.1.29:80                 Masq    1      0          0         
  -> 10.2.1.30:80                 Masq    1      0          0         
  -> 10.2.1.31:80                 Masq    1      0          0         
UDP  10.3.0.10:53 rr
  -> 10.2.0.3:53                  Masq    1      0          0         
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.3.0.1:443 rr persistent 10800
  -> 172.17.4.101:443             Masq    1      5          0         
TCP  10.3.0.10:53 rr
  -> 10.2.0.3:53                  Masq    1      0          0         
TCP  10.3.0.42:80 rr persistent 10800
  -> 10.2.1.22:80                 Masq    1      0          0         
  -> 10.2.1.23:80                 Masq    1      0          0         
  -> 10.2.1.24:80                 Masq    1      0          0         
  -> 10.2.1.25:80                 Masq    1      0          0         
  -> 10.2.1.26:80                 Masq    1      0          0         
  -> 10.2.1.27:80                 Masq    1      0          0         
  -> 10.2.1.28:80                 Masq    1      0          0         
  -> 10.2.1.29:80                 Masq    1      0          0         
  -> 10.2.1.30:80                 Masq    1      0          0         
  -> 10.2.1.31:80                 Masq    1      0          0         
UDP  10.3.0.10:53 rr
  -> 10.2.0.3:53

Testing connections to endpoints through ipvs service:

kubectl run client --command --image alpine -- sh -c 'while true; do wget ipvs; done'

ipvsadm shows all connections from one client remain on one endpoint.

do
kk exec $(basename ${i}) -- ipvsadm -ln --stats
done
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes
  -> RemoteAddress:Port
TCP  10.3.0.1:443                        0        0        0        0        0
  -> 172.17.4.101:443                    0        0        0        0        0
TCP  10.3.0.10:53                        0        0        0        0        0
  -> 10.2.0.3:53                         0        0        0        0        0
TCP  10.3.0.42:80                    14209   111769    74613  7207174  8334358
  -> 10.2.1.22:80                        2       12        8      774      894
  -> 10.2.1.23:80                        2       12        8      774      894
  -> 10.2.1.24:80                        2       12        8      774      894
  -> 10.2.1.25:80                        3       18       12     1161     1341
  -> 10.2.1.26:80                        3       18       12     1161     1341
  -> 10.2.1.27:80                        3       18       12     1161     1341
  -> 10.2.1.28:80                        3       18       12     1161     1341
  -> 10.2.1.29:80                        3       18       12     1161     1341
  -> 10.2.1.30:80                    14185   111625    74517  7197886  8323630
  -> 10.2.1.31:80                        3       18       12     1161     1341
UDP  10.3.0.10:53                    13640    37277    37276  2833052  3131346
  -> 10.2.0.3:53                     13640    37277    37276  2833052  3131346
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes
  -> RemoteAddress:Port
TCP  10.3.0.1:443                      481    36350    36499  4188520 16051448
  -> 172.17.4.101:443                  481    36350    36499  4188520 16051448
TCP  10.3.0.10:53                        0        0        0        0        0
  -> 10.2.0.3:53                         0        0        0        0        0
TCP  10.3.0.42:80                        0        0        0        0        0
  -> 10.2.1.22:80                        0        0        0        0        0
  -> 10.2.1.23:80                        0        0        0        0        0
  -> 10.2.1.24:80                        0        0        0        0        0
  -> 10.2.1.25:80                        0        0        0        0        0
  -> 10.2.1.26:80                        0        0        0        0        0
  -> 10.2.1.27:80                        0        0        0        0        0
  -> 10.2.1.28:80                        0        0        0        0        0
  -> 10.2.1.29:80                        0        0        0        0        0
  -> 10.2.1.30:80                        0        0        0        0        0
  -> 10.2.1.31:80                        0        0        0        0        0
UDP  10.3.0.10:53                        0        0        0        0        0
  -> 10.2.0.3:53                         0        0        0        0        0