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Check Link Hook

This example demonstrates how to process outgoing NHRP traffic in a scenario using one Tunnel with GRE encapsulation.

../../../../../_images/topology19.svg

Test Marks In NHRP Traffic

Description

In this scenario, a traffic policy was configured to log outgoing NHRP traffic, which is non-IP Layer 3 protocol. The special hook link-out can be used to process these outgoing frames.

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 192.168.100.10/24
set interfaces tunnel tun0 address 10.0.0.1/32
set interfaces tunnel tun0 encapsulation gre
set interfaces tunnel tun0 local-address 192.168.100.10
set interfaces tunnel tun0 nhrp
set interfaces tunnel tun0 traffic policy link-in LOG_NHRP
set interfaces tunnel tun0 traffic policy link-out LOG_NHRP
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy LOG_NHRP rule 1 log prefix NHRP__
set traffic policy LOG_NHRP rule 1 selector NHRP_SEL
set traffic selector NHRP_SEL rule 1 ether-type 8193

Note

NHRP packets use ethertype 8193 (0x2001).

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 address 192.168.100.20/24
set interfaces tunnel tun0 address 10.0.0.2/32
set interfaces tunnel tun0 encapsulation gre
set interfaces tunnel tun0 local-address 192.168.100.20
set interfaces tunnel tun0 nhrp holdtime 5
set interfaces tunnel tun0 nhrp nhs 10.0.0.1 nbma 192.168.100.10
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Run command protocols ip show nhrp at DUT0 and check if output matches the following regular expressions:

tun0\s+dynamic\s+10\.0\.0\.2
Show output
Iface      Type     Protocol         NBMA             Claimed NBMA     Expires(s)   Flags  Identity
tun0       local    10.0.0.1         192.168.100.10   192.168.100.10   -                   -
tun0       dynamic  10.0.0.2         192.168.100.20   192.168.100.20   5            UT

Step 4: Run command system journal show | cat at DUT0 and check if output matches the following regular expressions:

\[NHRP__-1\] ACCEPT IN=tun0 OUT=\w+
\[NHRP__-1\] ACCEPT IN= OUT=tun0
Show output
Feb 19 08:48:32.352303 osdx systemd-journald[2186]: Runtime Journal (/run/log/journal/69bd8e6fd19244c08e519827aa7e309f) is 2.4M, max 17.2M, 14.7M free.
Feb 19 08:48:32.352792 osdx systemd-journald[2186]: Received client request to rotate journal, rotating.
Feb 19 08:48:32.352837 osdx systemd-journald[2186]: Vacuuming done, freed 0B of archived journals from /run/log/journal/69bd8e6fd19244c08e519827aa7e309f.
Feb 19 08:48:32.363695 osdx OSDxCLI[55075]: User 'admin' executed a new command: 'system journal clear'.
Feb 19 08:48:32.629771 osdx OSDxCLI[55075]: User 'admin' executed a new command: 'system coredump delete all'.
Feb 19 08:48:32.927886 osdx OSDxCLI[55075]: User 'admin' entered the configuration menu.
Feb 19 08:48:33.051477 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces ethernet eth0 address 192.168.100.10/24'.
Feb 19 08:48:33.133681 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces tunnel tun0 traffic policy link-out LOG_NHRP'.
Feb 19 08:48:33.254156 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces tunnel tun0 traffic policy link-in LOG_NHRP'.
Feb 19 08:48:33.318618 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces tunnel tun0 address 10.0.0.1/32'.
Feb 19 08:48:33.443817 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces tunnel tun0 encapsulation gre'.
Feb 19 08:48:33.511328 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces tunnel tun0 local-address 192.168.100.10'.
Feb 19 08:48:33.617791 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set interfaces tunnel tun0 nhrp'.
Feb 19 08:48:33.682788 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set traffic policy LOG_NHRP rule 1 log prefix NHRP__'.
Feb 19 08:48:33.772638 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set traffic policy LOG_NHRP rule 1 selector NHRP_SEL'.
Feb 19 08:48:33.837285 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'set traffic selector NHRP_SEL rule 1 ether-type 8193'.
Feb 19 08:48:33.932012 osdx OSDxCLI[55075]: User 'admin' added a new cfg line: 'show working'.
Feb 19 08:48:34.000585 osdx ubnt-cfgd[105059]: inactive
Feb 19 08:48:34.113062 osdx systemd[1]: Reloading frr.service - FRRouting...
Feb 19 08:48:34.126490 osdx watchfrr[104937]: [NG1AJ-FP2TQ] Terminating on signal
Feb 19 08:48:34.227486 osdx frrinit.sh[105089]: Stopped watchfrr.
Feb 19 08:48:34.228580 osdx frrinit.sh[105089]: Starting watchfrr with command: '  /usr/lib/frr/watchfrr  -d  --min-restart-interval 1 --max-restart-interval 600 --timeout 600 --restart-timeout 600 zebra mgmtd nhrpd staticd'.
Feb 19 08:48:34.235861 osdx watchfrr[105107]: [T83RR-8SM5G] watchfrr 10.4.1 starting: vty@0
Feb 19 08:48:34.235913 osdx watchfrr[105107]: [QDG3Y-BY5TN] zebra state -> up : connect succeeded
Feb 19 08:48:34.235940 osdx watchfrr[105107]: [QDG3Y-BY5TN] mgmtd state -> up : connect succeeded
Feb 19 08:48:34.236007 osdx watchfrr[105107]: [ZCJ3S-SPH5S] nhrpd state -> down : initial connection attempt failed
Feb 19 08:48:34.236009 osdx watchfrr[105107]: [QDG3Y-BY5TN] staticd state -> up : connect succeeded
Feb 19 08:48:34.236190 osdx watchfrr[105107]: [YFT0P-5Q5YX] Forked background command [pid 105108]: /usr/lib/frr/watchfrr.sh restart nhrpd
Feb 19 08:48:34.240538 osdx frrinit.sh[105108]: Cannot stop nhrpd: pid file not found
Feb 19 08:48:34.241734 osdx watchfrr.sh[105113]: Cannot stop nhrpd: pid file not found
Feb 19 08:48:34.255441 osdx zebra[1799]: [V98V0-MTWPF] client 36 says hello and bids fair to announce only nhrp routes vrf=0
Feb 19 08:48:34.264487 osdx frrinit.sh[105118]: sh: line 1: ipsec: command not found
Feb 19 08:48:34.265596 osdx watchfrr[105107]: [QDG3Y-BY5TN] nhrpd state -> up : connect succeeded
Feb 19 08:48:34.265603 osdx watchfrr[105107]: [KWE5Q-QNGFC] all daemons up, doing startup-complete notify
Feb 19 08:48:34.266325 osdx frrinit.sh[105089]: Started watchfrr.
Feb 19 08:48:34.385830 osdx systemd[1]: Reloaded frr.service - FRRouting.
Feb 19 08:48:34.416807 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Feb 19 08:48:34.467179 osdx WARNING[105211]: No supported link modes on interface eth0
Feb 19 08:48:34.468975 osdx modulelauncher[105211]: osdx.utils.xos cmd error: /sbin/ethtool -A eth0 autoneg on
Feb 19 08:48:34.468988 osdx modulelauncher[105211]: Command '/sbin/ethtool -A eth0 autoneg on' returned non-zero exit status 76.
Feb 19 08:48:34.470216 osdx modulelauncher[105211]: osdx.utils.xos cmd error: /sbin/ethtool -s eth0 autoneg on advertise Asym_Pause off Pause off --
Feb 19 08:48:34.470225 osdx modulelauncher[105211]: Command '/sbin/ethtool -s eth0 autoneg on advertise Asym_Pause off Pause off --' returned non-zero exit status 75.
Feb 19 08:48:34.494226 osdx (udev-worker)[105239]: Network interface NamePolicy= disabled on kernel command line.
Feb 19 08:48:34.788949 osdx cfgd[1859]: [55075]Completed change to active configuration
Feb 19 08:48:34.803434 osdx OSDxCLI[55075]: User 'admin' committed the configuration.
Feb 19 08:48:34.832756 osdx OSDxCLI[55075]: User 'admin' left the configuration menu.
Feb 19 08:48:36.571380 osdx OSDxCLI[55075]: User 'admin' executed a new command: 'protocols ip show nhrp'.
Feb 19 08:48:37.388810 osdx kernel: [NHRP__-1] ACCEPT IN=tun0 OUT= MAC=45:00:00:74:43:23:40:00:40:2f:ad:c8:c0:a8:64:14:c0:a8:64:0a:00:00:20:01
Feb 19 08:48:37.388909 osdx kernel: [NHRP__-1] ACCEPT IN= OUT=tun0 MAC=45:01:00:00:00:00:40:00:40:2f:00:00:c0:a8:64:0a:c0:a8:64:14:00:00:20:01
Feb 19 08:48:37.388924 osdx kernel: [NHRP__-1] ACCEPT IN=tun0 OUT=eth0 MAC=00:01:08:00:00:00:00:00:00:40:00:70:2b:43:00:34:01:04:04:00:04:04:00:02
Feb 19 08:48:38.388816 osdx kernel: [NHRP__-1] ACCEPT IN=tun0 OUT= MAC=45:00:00:74:43:a7:40:00:40:2f:ad:44:c0:a8:64:14:c0:a8:64:0a:00:00:20:01
Feb 19 08:48:38.388910 osdx kernel: [NHRP__-1] ACCEPT IN= OUT=tun0 MAC=45:01:00:00:00:00:40:00:40:2f:00:00:c0:a8:64:0a:c0:a8:64:14:00:00:20:01
Feb 19 08:48:38.388924 osdx kernel: [NHRP__-1] ACCEPT IN=tun0 OUT=eth0 MAC=00:01:08:00:00:00:00:00:00:40:00:70:2b:42:00:34:01:04:04:00:04:04:00:02
Feb 19 08:48:38.646679 osdx OSDxCLI[55075]: User 'admin' executed a new command: 'protocols ip show nhrp'.

Step 5: Run command traffic policy show at DUT0 and check if output matches the following regular expressions:

1\s+NHRP_SEL\s+\b[^0]\d*
Show output
Policy LOG_NHRP -- ifc tun0 -- hook link-in prio very-high

---------------------------------------------------------------
rule   selector  pkts match  pkts eval  bytes match  bytes eval
---------------------------------------------------------------
1      NHRP_SEL           4          4          456         456
---------------------------------------------------------------
Total                     4          4          456         456

Policy LOG_NHRP -- ifc tun0 -- hook link-out prio very-high

---------------------------------------------------------------
rule   selector  pkts match  pkts eval  bytes match  bytes eval
---------------------------------------------------------------
1      NHRP_SEL           2          2          272         272
---------------------------------------------------------------
Total                     2          2          272         272
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