doc: add pods troubleshooting doc

Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>

Author: sknat

docs/README.md

@@ -13,7 +13,7 @@ troubleshooting commands and tools.
 - [Configuration](config), [General troubleshooting](troubleshooting.md)
 - [BGP with CalicoVPP](bgp), [troubleshooting BGP](bgp/troubleshooting.md)
 - [network model](network), [troubleshooting networking](network/troubleshooting.md)
-- [Pods connectivity](pods)
+- [Pods connectivity](pods), [troubleshooting pods](pods/troubleshooting.md)
 - [Services](services), [troubleshooting services](services/troubleshooting.md)
 - [Policies](policies), [troubleshooting policies](policies/troubleshooting.md)
 - [Metrics](metrics)

docs/pods/README.md

@@ -2,28 +2,37 @@
 
 CalicoVPP exposes three types of interaces
 
-- [tuntap](tuntap.md)
-- [memif](memif.md)
-- [vcl](vcl.md)
-- [tuntap](tuntap.md)
+- [tuntap](tuntap.md) - regular linux netdevs
+- [memif](memif.md) - performance oriented packet interaces
+- [vcl](vcl.md) - performance oriented host stack (TCP, UDP, TLS in VPP)
 
-## Pod interface configuration
+## Configuration
 
-As part of user config, you can set specific configuration for pod interfaces
-using pod annotations.
+The pod interface sizing can be confiugred with annotations in the pod
+manifest.
 
 ````yaml
-
 apiVersion: v1
 kind: Pod
 metadata:
  name: samplepod
  annotations:
  cni.projectcalico.org/vppInterfacesSpec: |-
  {
- "eth0": {"rx": 1, "tx": 2, "isl3": true }
+ "eth0": {
+ "rx": 1,
+ "tx": 1,
+ "rxqsz": 1024,
+ "txqsz": 1024,
+ "rxMode": "polling",
+ "isl3": true
+ }
  }
-
 ````
 
+- `tx` and `rx` set the number of queues the interface receives in VPP
+- `rxqsz` and `txqsz` set the number of buffers the interface receives in VPP
+- `rxMode` sets the way VPP reads from this interface (`polling` `adaptive` or `interrupt`)
+- `isL3` sets the interface mode L3 for `tun` (default) or L2 for `tap`
+
 Here is the full [specification reference](https://github.com/projectcalico/vpp-dataplane/blob/master/config/config.go)

docs/pods/memif.md

@@ -83,6 +83,10 @@ metadata:
  "cni.projectcalico.org/vppExtraMemifPorts": "tcp:4444-20000,udp:4444-20000"
 ````
 
+This meaning that ports `4444` to `20000` in both UDP and TCP will
+go to the memif interface while the rest of the traffic will flow
+normally to the tuntap.
+
 This is called PBL (Port based balancer).
 
 A pod supports having both memif and [vcl](vcl.md) interfaces at the same time
@@ -101,57 +105,6 @@ VPP api has a particular syntax for abstract sockets: using the keyword
 For example: `abstract:memif1,netns_name=/var/run/netns/cni-75e26661-4119-90a4-b9d2-0b00489f76f3`.
 This syntax appears in vppctl.
 
-## Troubleshooting memif interface creation
-
-To check abstract socket creation in linux, you can run the following command
-on the pod using memif:
-
-````bash
-lsof -U | grep memif
-vpp_main 420448 root 41u unix 0xffdd 0t0 30888503 @memif1 type=SEQPACKET
-````
-
-To check it in vpp cli:
-
-````bash
- _______ _ _ _____ ___ 
- __/ __/ _ \  (_)__ | | / / _ \/ _ \
- _/ _// // / / / _ \  | |/ / ___/ ___/
- /_/ /____(_)_/\___/ |___/_/ /_/ 
-
-vpp# sh memif
-sockets
- id listener filename
- 0 no /run/vpp/memif.sock
- 101 yes (1) abstract:memif1,netns_name=/var/run/netns/cni-75e61-4119-0b004
-
-interface memif1013904223/0
- socket-id 1013904223 id 0 mode ethernet
- flags admin-up
- listener-fd 41 conn-fd 0
- num-s2m-rings 0 num-m2s-rings 0 buffer-size 0 num-regions 0
-````
-
-To check memif interface creation:
-
-````bash
-vpp# sh int addr
-...
-...
-memif1013904223/0 (up): 
- unnumbered, use loop4
- L3 11.0.0.195/32 ip4 table-id 1649346937 fib-idx 12
- L3 fd20::58fd:b191:5c13:9cc2/128 ip6 table-id -1526094716 fib-idx 16
-...
-````
-
-In multinet case, this interface has a unique address and it attaches to a
-dummy interface.
-However, in PBL, memif interface is attached to the same interface as tun/tap.
-
-To check dummy interface created in multinet/memif, connect to the memif pod
-then type `ip address` to find memif dummy interfaces.
-
 ## Testing memif feature
 
 Testing depends on the way memif interface is consumed. We present three