From de8e80a54c96d2b75377e0e5319a64d32c88c690 Mon Sep 17 00:00:00 2001 From: Justin Iurman Date: Tue, 20 Jul 2021 21:43:00 +0200 Subject: [PATCH] ipv6: ioam: Documentation for new IOAM sysctls Add documentation for new IOAM sysctls: - ioam6_id and ioam6_id_wide: two per-namespace sysctls - ioam6_enabled, ioam6_id and ioam6_id_wide: three per-interface sysctls Example of IOAM configuration based on the following simple topology: _____ _____ _____ | | eth0 eth0 | | eth1 eth0 | | | A |.----------.| B |.----------.| C | |_____| |_____| |_____| 1) Node and interface IDs can be configured for IOAM: # IOAM ID of A = 1, IOAM ID of A.eth0 = 11 (A) sysctl -w net.ipv6.ioam6_id=1 (A) sysctl -w net.ipv6.conf.eth0.ioam6_id=11 # IOAM ID of B = 2, IOAM ID of B.eth0 = 21, IOAM ID of B.eth1 = 22 (B) sysctl -w net.ipv6.ioam6_id=2 (B) sysctl -w net.ipv6.conf.eth0.ioam6_id=21 (B) sysctl -w net.ipv6.conf.eth1.ioam6_id=22 # IOAM ID of C = 3, IOAM ID of C.eth0 = 31 (C) sysctl -w net.ipv6.ioam6_id=3 (C) sysctl -w net.ipv6.conf.eth0.ioam6_id=31 Note that "_wide" IDs equivalents can be configured the same way. 2) Each node can be configured to form an IOAM domain. For instance, we allow IOAM from A to C only (not the reverse path), i.e. enable IOAM on ingress for B.eth0 and C.eth0: (B) sysctl -w net.ipv6.conf.eth0.ioam6_enabled=1 (C) sysctl -w net.ipv6.conf.eth0.ioam6_enabled=1 3) An IOAM domain (e.g. ID=123) is defined and made known to each node: (A) ip ioam namespace add 123 (B) ip ioam namespace add 123 (C) ip ioam namespace add 123 4) Finally, an IOAM Pre-allocated Trace can be inserted in traffic sent by A when C (e.g. db02::2) is the destination: (A) ip -6 route add db02::2/128 encap ioam6 trace type 0x800000 ns 123 size 12 dev eth0 Signed-off-by: Justin Iurman Signed-off-by: David S. Miller --- Documentation/networking/ioam6-sysctl.rst | 26 +++++++++++++++++++++++ Documentation/networking/ip-sysctl.rst | 17 +++++++++++++++ 2 files changed, 43 insertions(+) create mode 100644 Documentation/networking/ioam6-sysctl.rst diff --git a/Documentation/networking/ioam6-sysctl.rst b/Documentation/networking/ioam6-sysctl.rst new file mode 100644 index 000000000000..c18cab2c481a --- /dev/null +++ b/Documentation/networking/ioam6-sysctl.rst @@ -0,0 +1,26 @@ +.. SPDX-License-Identifier: GPL-2.0 + +===================== +IOAM6 Sysfs variables +===================== + + +/proc/sys/net/conf//ioam6_* variables: +============================================= + +ioam6_enabled - BOOL + Accept (= enabled) or ignore (= disabled) IPv6 IOAM options on ingress + for this interface. + + * 0 - disabled (default) + * 1 - enabled + +ioam6_id - SHORT INTEGER + Define the IOAM id of this interface. + + Default is ~0. + +ioam6_id_wide - INTEGER + Define the wide IOAM id of this interface. + + Default is ~0. diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index b3fa522e4cd9..4bb4fa45cc29 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1926,6 +1926,23 @@ fib_notify_on_flag_change - INTEGER - 1 - Emit notifications. - 2 - Emit notifications only for RTM_F_OFFLOAD_FAILED flag change. +ioam6_id - INTEGER + Define the IOAM id of this node. Uses only 24 bits out of 32 in total. + + Min: 0 + Max: 0xFFFFFF + + Default: 0xFFFFFF + +ioam6_id_wide - LONG INTEGER + Define the wide IOAM id of this node. Uses only 56 bits out of 64 in + total. Can be different from ioam6_id. + + Min: 0 + Max: 0xFFFFFFFFFFFFFF + + Default: 0xFFFFFFFFFFFFFF + IPv6 Fragmentation: ip6frag_high_thresh - INTEGER