commit 00d28a78 added a check to see if there were any IPv6 routes added by RA (Router Advertisement) via an interface that had accept_ra set to something other than "2". The check was being done unconditionally, but it's only relevant if IPv6 forwarding is going to be turned on, and that will only happen if the network has an IPv6 address. ---  src/network/bridge_driver.c | 3 +--  1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index 0336ece..10e8f0e 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -2391,10 +2391,9 @@ networkStartNetworkVirtual(virNetworkDriverStatePtr driver,        /* If forward.type != NONE, turn on global IP forwarding */      if (network->def->forward.type != VIR_NETWORK_FORWARD_NONE) { -        if (!virNetDevIPCheckIPv6Forwarding()) +        if (v6present && !virNetDevIPCheckIPv6Forwarding())              goto err3; /* Precise error message already provided */   -          if (networkEnableIPForwarding(v4present, v6present) < 0) {              virReportSystemError(errno, "%s",                                   _("failed to enable IP forwarding"));