R5.0 : Svc chain: Svc chain group state for IPv6 also becomes 'group down' when health check failure for IPv4 is detected

[Ankit Jain]

Problem:

when any intermediate IPv4 link in the chain is down, it should not impact Ipv6 state/traffic.

leftvm--------svc instance in-net SI0 --svc chain instance in-net SI1----------- ------right vm

It was seen that when Ipv4 link of SI0's right intf was down, svc chain group state for Ipv6 was also marked down, and bacause of the same IPv6 re originated routes were also deleted, IPv6 traffic stopped flowing. Note that Ipv6 link was still up.

SI0:

root@box:/home/tc# ifconfig
eth0 Link encap:Ethernet HWaddr 02:f4:2f:69:a7:87
          inet addr:190.229.38.3 Bcast:190.229.38.255 Mask:255.255.255.0
          inet6 addr: 22f6:bf3b:2ec9:e38f::3/64 Scope:Global
          inet6 addr: fe80::f4:2fff:fe69:a787/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:1609 errors:0 dropped:0 overruns:0 frame:0
          TX packets:684 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:102519 (100.1 KiB) TX bytes:52955 (51.7 KiB)

eth1 Link encap:Ethernet HWaddr 02:3d:d3:a8:38:8e
          inet addr:35.139.225.4 Bcast:35.139.225.255 Mask:255.255.255.0
          inet6 addr: 207b:6ff6:d0f3:38c1::4/64 Scope:Global
          inet6 addr: fe80::3d:d3ff:fea8:388e/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:1240 errors:0 dropped:0 overruns:0 frame:0
          TX packets:586 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:70592 (68.9 KiB) TX bytes:37690 (36.8 KiB)

eth2 Link encap:Ethernet HWaddr 02:36:0c:f4:72:d1
          inet6 addr: fe80::36:cff:fef4:72d1/64 Scope:Link
          inet6 addr: 27f5:62a0:e9cd:42d2::4/64 Scope:Global
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:1636 errors:0 dropped:0 overruns:0 frame:0
          TX packets:873 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:123906 (121.0 KiB) TX bytes:71936 (70.2 KiB)

lo Link encap:Local Loopback
          inet addr:127.0.0.1 Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING MTU:65536 Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

root@box:/home/tc#
root@box:/home/tc#
root@box:/home/tc#
root@box:/home/tc# ping6 -s 56 -c 3 -W 1 27f5:62a0:e9cd:42d2::4 <--IPv6 link up
PING 27f5:62a0:e9cd:42d2::4 (27f5:62a0:e9cd:42d2::4): 56 data bytes
64 bytes from 27f5:62a0:e9cd:42d2::4: seq=0 ttl=64 time=0.079 ms
^Z[1]+ Stopped ping6 -s 56 -c 3 -W 1 27f5:62a0:e9cd:42d2::4
Left VM:
inet addr:35.139.225.3
inet6 addr: 207b:6ff6:d0f3:38c1::3/64 Scope:Global
inet6 addr: fe80::f6:adff:fe8f:f2df/64 Scope:Link

service_chain_list
src_virtual_network dest_virtual_network service_instance family src_rt_instance connected_rt_instance dest_rt_instance service_chain_addr state pending_reason service_chain_id connected_route more_specifics ext_connecting_rt_info_list aggregate_enable

default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-right_ctest-TestMultiInlineSVCIPv6-46261822-14664903
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-si-17376210
inet
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240:service-77745533-9f89-474c-9880-061cac30c973-default-domain_ctest-TestMultiInlineSVCIPv6-46261822_ctest-si-17376210
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-right_ctest-TestMultiInlineSVCIPv6-46261822-14664903:ctest-right_ctest-TestMultiInlineSVCIPv6-46261822-14664903
0.255.255.247
group down
-
77745533-9f89-474c-9880-061cac30c973
connected_route
service_chain_addr
0.255.255.247
connected_rt
connected_rt
prefix
0.255.255.247/32
last_modified
2018-Mar-16 11:19:03.516431
paths
paths
protocol last_modified local_preference med local_as peer_as peer_router_id source as_path next_hop label origin replicated primary_table secondary_tables communities origin_vn flags tunnel_encap sequence_no origin_vn_path pmsi_tunnel load_balance cluster_list originator_id edge_discovery edge_forwarding
XMPP
2018-Mar-16 11:19:03.516431
200
100
0
0
-
nodeh7
-
10.204.217.111
32
incomplete
false
secondary_tables
bgp.l3vpn.0
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240:service-77745533-9f89-474c-9880-061cac30c973-default-domain_ctest-TestMultiInlineSVCIPv6-46261822_ctest-si-78577652.inet.0
communities
encapsulation:gre
encapsulation:udp
secgroup:64512:8000002
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240
flags
None
tunnel_encap
gre
udp
-
origin_vn_path
pmsi_tunnel
type -
ar_type -
identifier -
label
0
flags
flags
load_balance
decision_type -
fields
fields
cluster_list
-
edge_discovery
edge_forwarding
more_specifics
prefix aggregate aggregate_rt more_specific_list
6.18.37.0/24
false
aggregate_rt
prefix -
last_modified -
paths
paths
more_specific_list
ext_connecting_rt_info_list
ext_rt_prefix ext_rt_svc_rt
6.18.37.3/32
ext_rt_svc_rt
prefix -
last_modified -
paths
paths
6.18.37.5/32
ext_rt_svc_rt
prefix -
last_modified -
paths
paths
0.255.255.248/32
ext_rt_svc_rt
prefix -
last_modified -
paths
paths
false
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-right_ctest-TestMultiInlineSVCIPv6-46261822-14664903
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-si-17376210
inet6
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240:service-77745533-9f89-474c-9880-061cac30c973-default-domain_ctest-TestMultiInlineSVCIPv6-46261822_ctest-si-17376210
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-right_ctest-TestMultiInlineSVCIPv6-46261822-14664903:ctest-right_ctest-TestMultiInlineSVCIPv6-46261822-14664903
::0.255.255.247
group down
-
77745533-9f89-474c-9880-061cac30c973
connected_route
service_chain_addr
::0.255.255.247
connected_rt
connected_rt
prefix
::0.255.255.247/128
last_modified
2018-Mar-16 11:19:03.653381
paths
paths
protocol last_modified local_preference med local_as peer_as peer_router_id source as_path next_hop label origin replicated primary_table secondary_tables communities origin_vn flags tunnel_encap sequence_no origin_vn_path pmsi_tunnel load_balance cluster_list originator_id edge_discovery edge_forwarding
XMPP
2018-Mar-16 11:19:03.653381
200
100
0
0
-
nodeh7
-
10.204.217.111
32
incomplete
false
secondary_tables
bgp.l3vpn-inet6.0
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240:service-77745533-9f89-474c-9880-061cac30c973-default-domain_ctest-TestMultiInlineSVCIPv6-46261822_ctest-si-78577652.inet6.0
communities
encapsulation:gre
encapsulation:udp
secgroup:64512:8000002
default-domain:ctest-TestMultiInlineSVCIPv6-46261822:ctest-left_ctest-TestMultiInlineSVCIPv6-46261822-17080240
flags
None
tunnel_encap
gre
udp
-
origin_vn_path
pmsi_tunnel
type -
ar_type -
identifier -
label
0
flags
flags
load_balance
decision_type -
fields
fields
cluster_list
-
edge_discovery
edge_forwarding
more_specifics
prefix aggregate aggregate_rt more_specific_list
27f5:62a0:e9cd:42d2::/64
false
aggregate_rt
prefix -
last_modified -
paths
paths
more_specific_list
ext_connecting_rt_info_list
ext_rt_prefix ext_rt_svc_rt
27f5:62a0:e9cd:42d2::5/128
ext_rt_svc_rt
prefix -
last_modified -
paths
paths
::0.255.255.248/128
ext_rt_svc_rt
prefix -
last_modified -
paths
paths
27f5:62a0:e9cd:42d2::3/128
ext_rt_svc_rt
prefix -
last_modified -
paths
paths
false

SI0:

Ping success from left vm to right via svc chain before Ipv4 health check failure:

ubuntu@ctest-left-vm-ctest-TestMultiInlineSVCIPv6-46261822-18074283:~$
ubuntu@ctest-left-vm-ctest-TestMultiInlineSVCIPv6-46261822-18074283:~$
ubuntu@ctest-left-vm-ctest-TestMultiInlineSVCIPv6-46261822-18074283:~$ ping 6.18.37.4
PING 6.18.37.4 (6.18.37.4) 56(84) bytes of data.
64 bytes from 6.18.37.4: icmp_req=1 ttl=63 time=1.53 ms
64 bytes from 6.18.37.4: icmp_req=2 ttl=63 time=0.628 ms
^Z
[3]+ Stopped ping 6.18.37.4
ubuntu@ctest-left-vm-ctest-TestMultiInlineSVCIPv6-46261822-18074283:~$ ping6 -s 56 -c 3 -W 1 27f5:62a0:e9cd:42d2::3
PING 27f5:62a0:e9cd:42d2::3(27f5:62a0:e9cd:42d2::3) 56 data bytes
64 bytes from 27f5:62a0:e9cd:42d2::3: icmp_seq=1 ttl=62 time=4.27 ms
64 bytes from 27f5:62a0:e9cd:42d2::3: icmp_seq=2 ttl=62 time=1.72 ms
64 bytes from 27f5:62a0:e9cd:42d2::3: icmp_seq=3 ttl=62 time=1.74 ms

Ping failure from left vm to right via svc chain after Ipv4 health check failure:

ubuntu@ctest-left-vm-ctest-TestMultiInlineSVCIPv6-46261822-18074283:~$ ping6 -s 56 -c 3 -W 1 27f5:62a0:e9cd:42d2::3
PING 27f5:62a0:e9cd:42d2::3(27f5:62a0:e9cd:42d2::3) 56 data bytes

[7]+ Stopped ping6 -s 56 -c 3 -W 1 27f5:62a0:e9cd:42d2::3
ubuntu@ctest-left-vm-ctest-TestMultiInlineSVCIPv6-46261822-18074283:~$ ping6 -s 56 -c 3 -W 1 27f5:62a0:e9cd:42d2::4
PING 27f5:62a0:e9cd:42d2::4(27f5:62a0:e9cd:42d2::4) 56 data bytes

--- 27f5:62a0:e9cd:42d2::4 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2015ms

[Ananth Suryanarayana (anantha-l)]

As per design as health check status is interface specific, not per afi per inrf (confirmed by agent team)