// setupKernelTunables validates kernel tunable flags are set as expected
// depending upon the specified option, it will either warn, error, or modify the kernel tunable flags
func setupKernelTunables(option KernelTunableBehavior) error {
desiredState := map[string]int{
utilsysctl.VmOvercommitMemory: utilsysctl.VmOvercommitMemoryAlways,
utilsysctl.VmPanicOnOOM: utilsysctl.VmPanicOnOOMInvokeOOMKiller,
}
errList := []error{}
for flag, expectedValue := range desiredState {
val, err := utilsysctl.GetSysctl(flag)
if err != nil {
errList = append(errList, err)
continue
}
if val == expectedValue {
continue
}
switch option {
case KernelTunableError:
errList = append(errList, fmt.Errorf("Invalid kernel flag: %v, expected value: %v, actual value: %v", flag, expectedValue, val))
case KernelTunableWarn:
glog.V(2).Infof("Invalid kernel flag: %v, expected value: %v, actual value: %v", flag, expectedValue, val)
case KernelTunableModify:
glog.V(2).Infof("Updating kernel flag: %v, expected value: %v, actual value: %v", flag, expectedValue, val)
err = utilsysctl.SetSysctl(flag, expectedValue)
if err != nil {
errList = append(errList, err)
}
}
}
return errors.NewAggregate(errList)
}
// NewProxier returns a new Proxier given an iptables Interface instance.
// Because of the iptables logic, it is assumed that there is only a single Proxier active on a machine.
// An error will be returned if iptables fails to update or acquire the initial lock.
// Once a proxier is created, it will keep iptables up to date in the background and
// will not terminate if a particular iptables call fails.
func NewProxier(ipt utiliptables.Interface, exec utilexec.Interface, syncPeriod time.Duration, masqueradeAll bool) (*Proxier, error) {
// Set the route_localnet sysctl we need for
if err := utilsysctl.SetSysctl(sysctlRouteLocalnet, 1); err != nil {
return nil, fmt.Errorf("can't set sysctl %s: %v", sysctlRouteLocalnet, err)
}
// Load the module. It's OK if this fails (e.g. the module is not present)
// because we'll catch the error on the sysctl, which is what we actually
// care about.
exec.Command("modprobe", "br-netfilter").CombinedOutput()
if err := utilsysctl.SetSysctl(sysctlBridgeCallIptables, 1); err != nil {
glog.Warningf("can't set sysctl %s: %v", sysctlBridgeCallIptables, err)
}
return &Proxier{
serviceMap: make(map[proxy.ServicePortName]*serviceInfo),
endpointsMap: make(map[proxy.ServicePortName][]string),
portsMap: make(map[localPort]closeable),
syncPeriod: syncPeriod,
iptables: ipt,
masqueradeAll: masqueradeAll,
}, nil
}