open-nomad/command/agent/util.go

54 lines
1.2 KiB
Go

package agent
import (
"fmt"
"math/rand"
"net"
"time"
)
// Returns a random stagger interval between 0 and the duration
func randomStagger(intv time.Duration) time.Duration {
return time.Duration(uint64(rand.Int63()) % uint64(intv))
}
// IpOfDevice returns a routable ip addr of a device
func ipOfDevice(name string) (net.IP, error) {
intf, err := net.InterfaceByName(name)
if err != nil {
return nil, err
}
addrs, err := intf.Addrs()
if err != nil {
return nil, err
}
if len(addrs) == 0 {
return nil, fmt.Errorf("no ips were detected on the interface: %v", name)
}
// Iterating through the IPs configured for that device and returning the
// the first ipv4 address configured. If no ipv4 addresses are configured,
// we return the first ipv6 addr if any ipv6 addr is configured.
var ipv6Addrs []net.IP
for _, addr := range addrs {
var ip net.IP
switch v := (addr).(type) {
case *net.IPNet:
ip = v.IP
if ip.To4() != nil {
return ip, nil
}
if ip.To16() != nil {
ipv6Addrs = append(ipv6Addrs, ip)
continue
}
case *net.IPAddr:
continue
}
}
if len(ipv6Addrs) > 0 {
return ipv6Addrs[0], nil
}
return nil, fmt.Errorf("no ips were detected on the interface: %v", name)
}