From 39808343b03078f992bc5e831ccdd843312f0714 Mon Sep 17 00:00:00 2001
From: Phil Sutter <phil@nwl.cc>
Date: Tue, 18 Dec 2018 12:16:30 +0100
Subject: [PATCH] extensions: TRACE: Point at xtables-monitor in documentation
With iptables-nft, logging of trace events is different from legacy.
Explain why and hint at how to receive events in this case.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>
(cherry picked from commit 9ac39888722ee9c7e97d9b8cb9eb4f33b582130a)
Signed-off-by: Phil Sutter <psutter@redhat.com>
---
extensions/libxt_TRACE.man | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/extensions/libxt_TRACE.man b/extensions/libxt_TRACE.man
index 8d590a52e26f8..5187a8d22802f 100644
--- a/extensions/libxt_TRACE.man
+++ b/extensions/libxt_TRACE.man
@@ -1,13 +1,20 @@
This target marks packets so that the kernel will log every rule which match
-the packets as those traverse the tables, chains, rules.
+the packets as those traverse the tables, chains, rules. It can only be used in
+the
+.BR raw
+table.
.PP
-A logging backend, such as ip(6)t_LOG or nfnetlink_log, must be loaded for this
-to be visible.
+With iptables-legacy, a logging backend, such as ip(6)t_LOG or nfnetlink_log,
+must be loaded for this to be visible.
The packets are logged with the string prefix:
"TRACE: tablename:chainname:type:rulenum " where type can be "rule" for
plain rule, "return" for implicit rule at the end of a user defined chain
and "policy" for the policy of the built in chains.
-.br
-It can only be used in the
-.BR raw
-table.
+.PP
+With iptables-nft, the target is translated into nftables'
+.B "meta nftrace"
+expression. Hence the kernel sends trace events via netlink to userspace where
+they may be displayed using
+.B "xtables-monitor --trace"
+command. For details, refer to
+.BR xtables-monitor (8).
--
2.21.0