The [NextHop] section is used to manipulate entries in the
kernel's "nexthop" tables. The [NextHop] section accepts the
following keys. Specify several [NextHop] sections to configure
several hops.
Id=
The id of the next hop. Takes an unsigned integer in the
range 1...4294967295. If left unspecified, then automatically
chosen by kernel.
Gateway=
As in the [Network] section.
Family=
Takes one of the special values "ipv4" or "ipv6". By default,
the family is determined by the address specified in
Gateway=. If Gateway= is not specified, then defaults to
"ipv4".
OnLink=
Takes a boolean. If set to true, the kernel does not have to
check if the gateway is reachable directly by the current
machine (i.e., attached to the local network), so that we can
insert the nexthop in the kernel table without it being
complained about. Defaults to "no".
Blackhole=
Takes a boolean. If enabled, packets to the corresponding
routes are discarded silently, and Gateway= cannot be
specified. Defaults to "no".
Group=
Takes a whitespace separated list of nexthop IDs. Each ID
must be in the range 1...4294967295. Optionally, each nexthop
ID can take a weight after a colon ("id[:weight]"). The
weight must be in the range 1...255. If the weight is not
specified, then it is assumed that the weight is 1. This
setting cannot be specified with Gateway=, Family=,
Blackhole=. This setting can be specified multiple times. If
an empty string is assigned, then the all previous
assignments are cleared. Defaults to unset.
