From f5a8c43f39937d97c9ed75e3fe8621945b42b0db Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Sun, 18 Oct 2015 18:25:58 +0200 Subject: networkd: IPv6 router discovery - follow IPv6AcceptRouterAdvertisemnt= The previous behavior: When DHCPv6 was enabled, router discover was performed first, and then DHCPv6 was enabled only if the relevant flags were passed in the Router Advertisement message. Moreover, router discovery was performed even if AcceptRouterAdvertisements=false, moreover, even if router advertisements were accepted (by the kernel) the flags indicating that DHCPv6 should be performed were ignored. New behavior: If RouterAdvertisements are accepted, and either no routers are found, or an advertisement is received indicating DHCPv6 should be performed, the DHCPv6 client is started. Moreover, the DHCP option now truly enables the DHCPv6 client regardless of router discovery (though it will probably not be very useful to get a lease withotu any routes, this seems the more consistent approach). The recommended default setting should be to set DHCP=ipv4 and to leave IPv6AcceptRouterAdvertisements unset. --- man/systemd.network.xml | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'man') diff --git a/man/systemd.network.xml b/man/systemd.network.xml index 7d081d22fe..5994869d97 100644 --- a/man/systemd.network.xml +++ b/man/systemd.network.xml @@ -227,7 +227,14 @@ yes, no, ipv4, or ipv6. - Please note that, by default, the domain name + Note that DHCPv6 will by default be triggered by Router + Advertisment, if that is enabled, regardless of this parameter. + By enabling DHCPv6 support explicitly, the DHCPv6 client will + be started regardless of the presence of routers on the link, + or what flags the routers pass. See + IPv6AcceptRouterAdvertisements=. + + Furthermore, note that by default the domain name specified through DHCP is not used for name resolution. See option below. @@ -414,6 +421,9 @@ When unset, the kernel default is used, and router advertisements are accepted only when local forwarding is disabled for that interface. + When router advertisements are accepted, they will + trigger the start of the DHCPv6 client if the relevant + flags are passed, or if no routers are found on the link. Takes a boolean. If true, router advertisements are accepted, when false, router advertisements are ignored, independently of the local forwarding state. -- cgit v1.2.3-54-g00ecf