From: David Gibson <david@gibson.dropbear.id.au>
To: passt-dev@passt.top, Stefano Brivio <sbrivio@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Subject: [PATCH v4 3/7] test: Wait for DAD on DHCPv6 addresses
Date: Thu, 17 Oct 2024 16:33:00 +1100 [thread overview]
Message-ID: <20241017053304.909386-4-david@gibson.dropbear.id.au> (raw)
In-Reply-To: <20241017053304.909386-1-david@gibson.dropbear.id.au>
After running dhclient -6 we expect the DHCPv6 assigned address to be
immediately usable. That's true with the Fedora dhclient-script (and the
upstream ISC DHCP one), however it's not true with the Debian
dhclient-script. The Debian script can complete with the address still
in "tentative" state, and the address won't be usable until Duplicate
Address Detection (DAD) completes. That's arguably a bug in Debian (see
link below), but for the time being we need to work around it anyway.
We usually get away with this, because by the time we do anything where the
address matters, DAD has completed. However, it's not robust, so we should
explicitly wait for DAD to complete when we get an DHCPv6 address.
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1085231
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
test/passt/dhcp | 2 ++
test/pasta/dhcp | 2 ++
test/two_guests/basic | 3 +++
3 files changed, 7 insertions(+)
diff --git a/test/passt/dhcp b/test/passt/dhcp
index e05a4bb..9925ab9 100644
--- a/test/passt/dhcp
+++ b/test/passt/dhcp
@@ -49,6 +49,8 @@ check [ "__SEARCH__" = "__HOST_SEARCH__" ]
test DHCPv6: address
guest /sbin/dhclient -6 __IFNAME__
+# Wait for DAD to complete
+guest while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
gout ADDR6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__IFNAME__").addr_info[] | select(.prefixlen == 128).local] | .[0]'
hout HOST_ADDR6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__HOST_IFNAME6__").addr_info[] | select(.scope == "global" and .deprecated != true).local] | .[0]'
check [ "__ADDR6__" = "__HOST_ADDR6__" ]
diff --git a/test/pasta/dhcp b/test/pasta/dhcp
index 41556b8..d4f3ad5 100644
--- a/test/pasta/dhcp
+++ b/test/pasta/dhcp
@@ -35,6 +35,8 @@ check [ __MTU__ = 65520 ]
test DHCPv6: address
ns /sbin/dhclient -6 --no-pid __IFNAME__
+# Wait for DAD to complete
+ns while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
hout HOST_IFNAME6 ip -j -6 route show|jq -rM '[.[] | select(.dst == "default").dev] | .[0]'
nsout ADDR6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__IFNAME__").addr_info[] | select(.prefixlen == 128).local] | .[0]'
hout HOST_ADDR6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__HOST_IFNAME6__").addr_info[] | select(.scope == "global" and .deprecated != true).local] | .[0]'
diff --git a/test/two_guests/basic b/test/two_guests/basic
index ac50ff8..9ba5efe 100644
--- a/test/two_guests/basic
+++ b/test/two_guests/basic
@@ -40,6 +40,9 @@ guest1 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1;
guest2 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
guest1 /sbin/dhclient -6 __IFNAME1__
guest2 /sbin/dhclient -6 __IFNAME2__
+# Wait for DAD to complete on the DHCP address
+guest1 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
+guest2 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
g1out ADDR1_6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__IFNAME1__").addr_info[] | select(.prefixlen == 128).local] | .[0]'
g2out ADDR2_6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__IFNAME2__").addr_info[] | select(.prefixlen == 128).local] | .[0]'
hout HOST_ADDR6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__HOST_IFNAME6__").addr_info[] | select(.scope == "global" and .deprecated != true).local] | .[0]'
--
@@ -40,6 +40,9 @@ guest1 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1;
guest2 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
guest1 /sbin/dhclient -6 __IFNAME1__
guest2 /sbin/dhclient -6 __IFNAME2__
+# Wait for DAD to complete on the DHCP address
+guest1 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
+guest2 while ip -j -6 addr show tentative | jq -e '.[].addr_info'; do sleep 0.1; done
g1out ADDR1_6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__IFNAME1__").addr_info[] | select(.prefixlen == 128).local] | .[0]'
g2out ADDR2_6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__IFNAME2__").addr_info[] | select(.prefixlen == 128).local] | .[0]'
hout HOST_ADDR6 ip -j -6 addr show|jq -rM '[.[] | select(.ifname == "__HOST_IFNAME6__").addr_info[] | select(.scope == "global" and .deprecated != true).local] | .[0]'
--
2.47.0
next prev parent reply other threads:[~2024-10-17 5:33 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-17 5:32 [PATCH v4 0/7] Don't expose container loopback services to the host David Gibson
2024-10-17 5:32 ` [PATCH v4 1/7] arp: Fix a handful of small warts David Gibson
2024-10-17 8:45 ` Stefano Brivio
2024-10-18 0:43 ` David Gibson
2024-10-17 5:32 ` [PATCH v4 2/7] test: Explicitly wait for DAD to complete on SLAAC addresses David Gibson
2024-10-17 5:33 ` David Gibson [this message]
2024-10-17 8:45 ` [PATCH v4 3/7] test: Wait for DAD on DHCPv6 addresses Stefano Brivio
2024-10-18 1:13 ` David Gibson
2024-10-17 5:33 ` [PATCH v4 4/7] passt.1: Mark --stderr as deprecated more prominently David Gibson
2024-10-17 5:33 ` [PATCH v4 5/7] passt.1: Clarify and update "Handling of local addresses" section David Gibson
2024-10-17 5:33 ` [PATCH v4 6/7] test: Clarify test for spliced inbound transfers David Gibson
2024-10-17 5:33 ` [PATCH v4 7/7] fwd: Direct inbound spliced forwards to the guest's external address David Gibson
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