From 9ba749a49774c79ef1b3ce25589b65a79ad3aac2 Mon Sep 17 00:00:00 2001 From: Yong Tang Date: Sun, 31 Jul 2016 16:24:17 -0700 Subject: [PATCH] Better error messages when IP address autodetection fails This fix tries to improve error messages when IP address autodetection fails, as is specified in 25141. Previously, error messages only indicate that multiple IPs exist when autodetection fails. In this fix, if one interface consists of multiple addresses or multiple interfaces consist of addresses, the error messages output the address names and interface names so that end user could take notice. This fix is verified manually. When multiple addresses exist on multiple interfaces: ``` $ sudo docker swarm init Error response from daemon: could not choose an IP address to advertise since this system has multiple addresses on different interfaces (192.168.186.128 on ens33 and 192.168.100.199 on eth10) - specify one with --advertise-addr ``` When multiple addresses exist on single interface: ``` $ sudo docker swarm init Error response from daemon: could not choose an IP address to advertise since this system has multiple addresses on interface ens33 (192.168.186.128 and 192.168.55.199) - specify one with --advertise-addr ``` This fix fixes 25141. Signed-off-by: Yong Tang (cherry picked from commit 59db01049ac6a8e54490565dc44661f780c13734) Signed-off-by: Tibor Vass --- daemon/cluster/listen_addr.go | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/daemon/cluster/listen_addr.go b/daemon/cluster/listen_addr.go index c3dbe083ea..2c93d0d828 100644 --- a/daemon/cluster/listen_addr.go +++ b/daemon/cluster/listen_addr.go @@ -8,7 +8,6 @@ import ( var ( errNoSuchInterface = errors.New("no such interface") - errMultipleIPs = errors.New("could not choose an IP address to advertise since this system has multiple addresses") errNoIP = errors.New("could not find the system's IP address") errMustSpecifyListenAddr = errors.New("must specify a listening address because the address to advertise is not recognized as a system address") errBadListenAddr = errors.New("listen address must be an IP address or network interface (with optional port number)") @@ -159,6 +158,7 @@ func (c *Cluster) resolveSystemAddr() (net.IP, error) { } var systemAddr net.IP + var systemInterface net.Interface // List Docker-managed subnets v4Subnets := c.config.NetworkSubnetsProvider.V4Subnets() @@ -197,7 +197,7 @@ ifaceLoop: } if interfaceAddr4 != nil { - return nil, errMultipleIPs + return nil, fmt.Errorf("could not choose an IP address to advertise since this system has multiple addresses on interface %s (%s and %s)", intf.Name, interfaceAddr4, ipAddr.IP) } interfaceAddr4 = ipAddr.IP @@ -212,7 +212,7 @@ ifaceLoop: } if interfaceAddr6 != nil { - return nil, errMultipleIPs + return nil, fmt.Errorf("could not choose an IP address to advertise since this system has multiple addresses on interface %s (%s and %s)", intf.Name, interfaceAddr6, ipAddr.IP) } interfaceAddr6 = ipAddr.IP @@ -223,14 +223,16 @@ ifaceLoop: // and exactly one IPv6 address, favor IPv4 over IPv6. if interfaceAddr4 != nil { if systemAddr != nil { - return nil, errMultipleIPs + return nil, fmt.Errorf("could not choose an IP address to advertise since this system has multiple addresses on different interfaces (%s on %s and %s on %s)", systemAddr, systemInterface.Name, interfaceAddr4, intf.Name) } systemAddr = interfaceAddr4 + systemInterface = intf } else if interfaceAddr6 != nil { if systemAddr != nil { - return nil, errMultipleIPs + return nil, fmt.Errorf("could not choose an IP address to advertise since this system has multiple addresses on different interfaces (%s on %s and %s on %s)", systemAddr, systemInterface.Name, interfaceAddr6, intf.Name) } systemAddr = interfaceAddr6 + systemInterface = intf } }