ifdown calls bind's rndc, which tries to access TCP port 953 on lo.
If these packets are dropped by the firewall we have to wait for the TCP
connections to time out, which takes quite a while.
With -W we reduce timeouts when we don't expect a response. With -i the
interval between pings is reduced (mostly in case of auto=route where
the first ping yields no reply).
We will use this to set some defaults (e.g. timeouts to make testing
negative tests quicker). We don't want these settings to show up in the
configs of the actual scenarios though.
Adds XFRM state/policy flush when terminating which caused tests to fail
due to the check added with 9086f060d3 ("testing: Let test scenarios
fail if IPsec SAs or policies are not removed").
The default of 56 bytes already exceeds the threshold of 90 bytes (8 bytes
ICMP + 40 bytes IPv6 = 104 bytes). By reducing the size we make sure the
packet is not compressed (40 + 8 + 40 = 88).
This also fixes a strange failure of this scenario due to the recently
added post-test `ip xfrm state` check. The kernel stores a reference to
the used SAs on the inbound skbuffs and since these are garbage collected
it could take a while until all references to an SA disappear and the SA
is finally destroyed. But while SAs might not get destroyed immediately
when we delete them, they are actually marked as dead and therefore won't
show up in `ip xfrm state`. However, that's not the case for the tunnel
SAs the kernel attaches to IPComp SAs, which we don't explicitly delete,
and which aren't modified by the kernel until the IPComp SA is destroyed.
So what happened when the last ping unintentionally got compressed is that
the skbuff had a reference to the IPComp SA and therefore the tunnel SA.
This skbuff often was destroyed after the `ip xfrm state` check ran and
because the tunnel SA would still get reported the test case failed.
running_any is satisfied if at least one host is running. We could
easily add a running_all() helper to check if all hosts are running if
it turns out that's not strong enough.
This allows us to do modifications to the kernel tree and rebuild that kernel
using make-testing. We can even have a git kernel tree in a directory to
do kernel development.