Networkd

layer 0 network daemon.

Dependency

• ip (iproute-3.10.0-13.el7.x86_64)
• arping (iputils-20121221-6.el7.x86_64)
• iptables (iptables-1.4.21-13.el7.x86_64)
• docker
• etcd
• lainlet

Float IP

1. watch etcd/lainlet key: /lain/config/vips/*
2. watch procs in /lain/config/vips/*
3. config node vip

virtual ip config protocol

• key: /lain/config/vips/{IP}

• value:

  {
      "app": "APP1", # lain app name, required
      "proc": "PROC1", # lain app proc name, required
      "ports": [
          {
              "src": "PORT1", # source port (virtual ip/host port), required
              "proto": "tcp", # port protocol, optional, default: `tcp`, options: `tcp`, `udp`
              "dest": "APPPORT1" # destination port (lain app port), optional, default: `PORT1(current virtual ip port)`
          },
          {
              ...
          }
      ], # lain app ports, required
      "excluded_nodes": ["NODE1", "NODE2"] # optional, default: `[]`
  }
  

interface

TBD

PS: only support default interface now

example

vip: 192.168.10.254

1. lock key
   • key: /lain/networkd/vips/192.168.10.254.lock
   • value:node1 # node hostname
2. config key

   • key: /lain/config/vips/192.168.10.254

   • value: json # ip config

     {
         "app": "resource.elb.webrouter",
         "proc": "haproxy",
         "ports": [
             {
                 "src": "80",
                 "proto": "tcp"
             },
             {
                 "src": "443",
                 "proto": "tcp"
             },
             {
                 "src": "5555",
                 "proto": "udp",
                 "dest": "53"
             },
         ]
     }
     

Dns

Networkd contains a embedded dns server similar to dnsmasq. All resolvable domains from etcd are configured in /lain/config/domains.

1. key
   • exact domain, e.g., /lain/config/domains/etcd.lain, /lain/config/domains/docker.lain.
   • wildcard domain begins with *., e.g., /lain/config/domains/*.lain, /lain/config/domains/*.lain.local.
2. value
   • type `` to resolve to the specified IPs, e.g., {"ips":["10.131.0.72"],"type":""}.
   • type node to resolve to node IP, e.g., {"ips":[],"type":"node"}.
   • type webrouter to resolve to webrouter IPs, e.g., {"ips":[],"type":"webrouter"}.
3. dump dns config
   • curl http://127.0.0.1:3000/v1/dns/config

Tinydns

dynamic dns server conf of tinydns app

Swarm

1. dynamic dns host conf of swarm manager
   1. swarm.lain
2. /lain/swarm/docker/swarm/leader

Deployd

1. dynamic dns host conf of deployd
   1. deployd.lain
2. /lain/deployd/leader

Webrouter

1. dynamic webrouter.lain when no vip for webrouter

Resolv.conf

1. Watch /etc/resolv.conf
2. Ensure nameserver 127.0.0.1 in the first line.
3. synchronize name servers from /etc/resolv.conf
4. Remove rotate options

TODO

1. Split lock & health goroutine
2. Print iptables acl rules

License

Networkd is released under the MIT license.