IpArp not learning IP

[GONÇALO_NUNO_CO]

Hi,

i am trying to troubleshoot why IPARP is not showing the IP addresses of edge devices.
Slot-1 SEDUCA050100.3 # sh iparp stats ports 3:23
IP ARP Port Statistics Thu Mar 8 08:55:47 2018
Port Link State Active ARP Total Dynamic Static
===============================================================================
3:23 A 0 0 0
===============================================================================If i do a "sh fdb port 3:23" i can see the mac of the connected device, but for some reason IPARP is not storing the Mac and the IP address of the connected device, this is hapenning on all ports, also and since IPARP doest not store any IP addresses, IdMgr doesnt show them too.

I have all vlan interfaces configured with an ip address and IPARP is enabled by default on the switch.

I wondering what commands can i use to troubleshoot this situation.

Br,
Gonçalo Reis

[davidj_cogliane]

You have a fair amount going on there but I don't see what the issue could be. The fact that it varies based on code version makes me think it is a bug that TAC would need to look at.

I do not fully understand what you mean by "If i configure and Vlan assign an ip address to that vlan, i can see the IP of the connected device, the problem arises when i put the default port configuration that i use on my network, this is when the iparp loses all information off the connected device."

This makes it sound like you see the arp entry until you apply the default port config. So can you narrow it down by adding one command at a time and checking to see when the arp entry disappears? This does not mean its not a bug, but would help narrow down what causes the bug so TAC could better assist you.

[GONÇALO_NUNO_CO]

I have already reproduced this on a lab environment and narrow down all the configuration line by line and found that the policy applied to the port is preventing the iparp from learning the IP address of end devices, if i remove the policy rule i can see the ip address of the directly connected device.

However what is annoying me is that on a production switch with the same EXOS version and configuration the behaviour is not same, and when i remove the policy rule from the port i am still unable to see the ip address.

To me this sounds like a bug and so far i havent found which configuration line is triggering it.

[M_Nees]

Do you try to reproduce this issue on a small lab switch ?
On a lab switch it will be easier to troubleshoot.

If yes enable debugging for ARP or mirror the client traffic to better what is happened.

[GONÇALO_NUNO_CO]

Hi David,

The EXOS version i am using is 22.4.1.4. All end devices have static IP addresses, and i can see them in the upstream switches, they dont have any connectivity problems.

On my original post you can see that port 3:23 is with link, but the iparp hasnt learn anything from that port, this can be confirmed with the command you suggested.
Slot-1 SEDUCA050100.1 # sh iparp port 3:23
VR Destination Mac Age Static VLAN VID Port
Dynamic Entries : 210 Static Entries : 0
Pending Entries : 0
In Request : 36704719 In Response : 34498
Out Request : 5403 Out Response : 3436
Failed Requests : 0
Proxy Answered : 0
Rx Error : 0 Dup IP Addr : 0.0.0.0
Rejected Count : 33098174 Rejected IP : 147.96.23.2
Rejected Port : 1:49 Rejected I/F : Docencia
Max ARP entries : 8192 Max ARP pending entries : 256
ARP address check: Disabled ARP refresh : Enabled
Timeout : 20 minutes ARP Sender-Mac Learning : Disabled
Locktime : 1000 milliseconds
Retransmit Time : 1000 milliseconds
Reachable Time : 900000 milliseconds (Auto)
Fast Convergence : Off If i configure and Vlan assign an ip address to that vlan, i can see the IP of the connected device, the problem arises when i put the default port configuration that i use on my network, this is when the iparp loses all information off the connected device. This is the deafult port configuration:
Slot-1 SEDUCA050100.2 # sh conf | in "3:23"
disable snmp traps port-up-down port 3:23
configure port 3:23 rate-limit flood broadcast 120 out-actions log trap
configure port 3:23 rate-limit flood multicast 120 out-actions log trap
configure port 3:23 rate-limit flood unknown-destmac 120 out-actions log trap
configure vlan DAPs add ports 3:23,3:45-47,4:10-13 untagged
configure port 3:23 link-flap-detection on
configure port 3:23 link-flap-detection interval 60 threshold 5
configure port 3:23 link-flap-detection action add log trap
enable mac-locking ports 3:23
configure mac-locking ports 3:23 first-arrival limit-learning 1
configure mac-locking ports 3:23 first-arrival aging enable
configure mac-locking ports 3:23 trap violation on
configure mac-locking ports 3:23 log violation on
configure policy rule admin-profile port 3:23 mask 16 port-string 3:23 admin-pid 8
disable edp ports 3:23
disable lldp ports 3:23
enable nodealias ports 3:23
configure nodealias ports 3:23 maxentries 20
configure stpd s0 ports link-type edge 3:23
configure stpd s0 ports edge-safeguard enable 3:23
configure stpd s0 ports bpdu-restrict enable 3:23I dont have any problem on the switches that are on EXOS 21.x.x version and all of them have the same configuration regardless of the EXOS version.

Let me know if i was clear enough with my explation

Br,
Gonçalo Reis

[Nick_Yakimenko]

iparp works only if you have an ip interface in the corresponding vlan