func ensureLink(vxlan *netlink.Vxlan) (*netlink.Vxlan, error) {
err := netlink.LinkAdd(vxlan)
if err == syscall.EEXIST {
// it's ok if the device already exists as long as config is similar
existing, err := netlink.LinkByName(vxlan.Name)
if err != nil {
return nil, err
}
incompat := vxlanLinksIncompat(vxlan, existing)
if incompat == "" {
return existing.(*netlink.Vxlan), nil
}
// delete existing
log.Warningf("%q already exists with incompatable configuration: %v; recreating device", vxlan.Name, incompat)
if err = netlink.LinkDel(existing); err != nil {
return nil, fmt.Errorf("failed to delete interface: %v", err)
}
// create new
if err = netlink.LinkAdd(vxlan); err != nil {
return nil, fmt.Errorf("failed to create vxlan interface: %v", err)
}
} else if err != nil {
return nil, err
}
ifindex := vxlan.Index
link, err := netlink.LinkByIndex(vxlan.Index)
if err != nil {
return nil, fmt.Errorf("can't locate created vxlan device with index %v", ifindex)
}
var ok bool
if vxlan, ok = link.(*netlink.Vxlan); !ok {
return nil, fmt.Errorf("created vxlan device with index %v is not vxlan", ifindex)
}
return vxlan, nil
}
func (dev *vxlanDevice) Destroy() {
netlink.LinkDel(dev.link)
}