From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: passt.top; dkim=fail reason="key not found in DNS" header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202312 header.b=A4kxpV8k; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 8F1615A027F for ; Wed, 21 Aug 2024 06:20:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202312; t=1724214023; bh=AZtfTH441ojS+X7UiHYSe8R6FySpoMFF9nAcdvP3TgM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A4kxpV8k/e78AiqO2A1dk41qZ/TMBxC6tObFE3kU478yNrXRKa6jKJzooTFBr+xxN EUmUnFdGyPSBEk6FE5Gl3TejE+Z2OjeEEsnoOmuVg8M1laPkIOsFzllEcjLCi6jFTZ Ep0pb0Ptb65QtYaVtUenxJkFuCUR/YowQhx1QmN49rE7KEq9Mt9lUiVzZGvM5PA3Pg s+GIgLYunXKi9Dtt4gQftOMWGMvwtXiJ/cKHScUUaFkueLPK5SzEADaM48J44wVfNn tuK4d6zibYp/8Mqn8eB5WKUoMosQM6F18WwdVK5LfXFS9TB2ZadBcmcl92JT6xYFwL K9JusB00qE1kQ== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4WpY5z2sY7z4x8X; Wed, 21 Aug 2024 14:20:23 +1000 (AEST) From: David Gibson To: passt-dev@passt.top, Stefano Brivio Subject: [PATCH v2 20/23] test: Reconfigure IPv6 address after changing MTU Date: Wed, 21 Aug 2024 14:20:16 +1000 Message-ID: <20240821042020.718422-21-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240821042020.718422-1-david@gibson.dropbear.id.au> References: <20240821042020.718422-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: PBJCLLJLWFD2L5FDAQBZ27OVEBDITJEK X-Message-ID-Hash: PBJCLLJLWFD2L5FDAQBZ27OVEBDITJEK X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Paul Holzinger , David Gibson X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: In the TCP throughput tests, we adjust the guest's MTU in order to test various packet sizes. Some of those are below 1280 which causes IPv6 to be deconfigured on the guest interface. When we increase it above 1280 again, IPv6 is re-enabled and we get an address in the right prefix with NDP, but we don't get exactly the expected address back - that's only communicated with --config-net or DHCPv6. With changes to how we handle NAT this can cause some of the IPv6 tests to fail, because they don't use the address that passt/pasta expects, and the guest doesn't initiate any traffic which allows us to learn what the new address is. Work around this by re-invoking dhclient -6 between adjusting the MTU and running IPv6 test cases. Signed-off-by: David Gibson --- test/perf/passt_tcp | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/test/perf/passt_tcp b/test/perf/passt_tcp index 695479f3..635998e1 100644 --- a/test/perf/passt_tcp +++ b/test/perf/passt_tcp @@ -112,6 +112,10 @@ bw __BW__ 7.0 8.0 iperf3k ns +# Reducing MTU below 1280 deconfigures IPv6, get our address back +guest dhclient -6 -x +guest dhclient -6 __IFNAME__ + tl TCP RR latency over IPv4: guest to host lat - lat - -- 2.46.0