DHCP relay agent check command

[Translator]

Could you please tell me the command to check if DHCP relay is working?
I couldn't find the answer even after searching, so could you help me?

Reference information
Model number: C9300
OS: version 17.9

<Japanese>
Whether DHCP Relay is Working
Could you give me the command to investigate?
You can only find out how to set up the relay agent.

reference information
Model: C9300
OS: version 17.9

[paul driver]

Hello @liviu.gheorghe 

---

@liviu.gheorghe wrote:

I the ip dhcp relay address isn't available on routers running IOS or IOS XE.

FYI...

IOS
Router#sh version | in Version| program
Cisco IOS Software, IOSv Software (VIOS-ADVENTERPRISEK9-M), Version 15.7(3)M3, RELEASE SOFTWARE (fc2)
ROM: Bootstrap program is IOSv

Router#sh run int gig0/0 | in help
ip helper-address 1.1.1.1

Router#sh ip dhcp relay information trusted-sources
List of trusted sources of relay agent information option

CSR
Cisco IOS Software [Everest], Virtual XE Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.1, RELEASE SOFTWARE (fc2)
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
GPL code under the terms of GPL Version 2.0. For more details, see the

Router#sh run int gi1 | in help
ip helper-address 1.1.1.1

Router#sh ip dhcp relay information trusted-sources
List of trusted sources of relay agent information option

8000v
Router#sh version | in Version| program
Cisco IOS XE Software, Version 17.06.03a
Cisco IOS Software [Bengaluru], Virtual XE Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 17.6.3a, RELEASE SOFTWARE (fc1)
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
GPL code under the terms of GPL Version 2.0. For more details, see the

Router#sh run int gig1 | in help
ip helper-address 1.1.1.1

Router#sh ip dhcp relay information trusted-sources
List of trusted sources of relay agent information option:

Cat9000
Switch#sh version | in Version| program
Cisco IOS XE Software, Version 17.10.01prd7
Cisco IOS Software [Dublin], Catalyst L3 Switch Software (CAT9K_IOSXE), Version 17.10.1prd7, RELEASE SOFTWARE (fc1)
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
GPL code under the terms of GPL Version 2.0. For more details, see the
Switch Ports Model SW Version SW Image Mode

Switch#sh run int gig0/0 | in help
ip helper-address 1.1.1.1

Switch#sh ip dhcp relay information trusted-sources
List of trusted sources of relay agent information option:

[liviu.gheorghe]

Hello @paul driver ,

I was referring to the ip dhcp relay address interface configuration command as described in this document, not the ip helper-address.

https://www.cisco.com/c/en/us/td/docs/switches/lan/csbms/CBS_250_350/CLI/cbs-250-cli/dhcp-relay-commands.html

[vishalbhandari]

@Translator You can check if DHCP relay is working on your Cisco C9300 switch using the following commands:

1. Check if DHCP relay is configured:

   show running-config | include ip helper-address

   This will show if the ip helper-address command is applied to the interface.

2. Check DHCP relay statistics:

   show ip dhcp relay statistics

   This will display the number of DHCP requests and replies forwarded by the relay agent.

3. Debug DHCP relay traffic (use with caution in production):

   debug ip dhcp server packets debug ip dhcp relay

   These commands will show live DHCP relay activity. Use undebug all to turn off debugging when done.

Let me know if you need further clarification!

[suzuki2502]

Thank you!

I was unable to get "show ip dhcp relay statistics" to work on the C2960, but I'll try it on the C9300.