DHCP adds an external address by itself. Why?

[kastamonu.university]

Hello there,
I have a WS-C3560X-48T-L(15.2(4)E10-C3560E-UNIVERSALK9-M). I distribute IP to IP phones with this device. But I have a problem. It adds a self-excluded string when there is no string I excluded. I hope I could explain. I didn't add the "Excluded-13" seen below.
Output of "sh ip dhcp pool":
sh ip dhcp pool

Pool IP_TEL :
Utilization mark (high/low): 100 / 0
Subnet size (first/next): 0 / 0
Total addresses : 62
Leased addresses : 30
Excluded addresses : 13
Pending event: none
1 subnet is currently in the pool :
Current index IP address range Leased/Excluded/Total
10.82.8.212 10.82.8.193 - 10.82.8.254 30 / 13 / 62

and dhcp config:
ip dhcp pool IP_TEL
network 10.82.8.192 255.255.255.192
default-router 10.82.8.193
option 150 ip 10.221.56.4 10.221.56.134
lease 7

Thanks everyone in advance.

[Rosseti]

sh run | inc ip dhcp excluded-address

[kastamonu.university]

the output of this command is empty. because I did not enter such a command.

[Rosseti]

sh ip dhcp conflict

[kastamonu.university]

sh ip dhcp conflict
IP address Detection method Detection time VRF
10.82.8.194 Ping Nov 30 2021 01:02 PM
10.82.8.195 Ping Nov 30 2021 01:02 PM
10.82.8.196 Ping Nov 30 2021 01:02 PM
10.82.8.197 Ping Nov 30 2021 01:02 PM
10.82.8.253 Ping Nov 30 2021 11:44 PM
10.82.8.200 Ping Nov 30 2021 11:44 PM
10.82.8.234 Ping Dec 01 2021 12:45 AM
10.82.8.233 Ping Dec 01 2021 12:45 AM
10.82.8.227 Ping Dec 01 2021 12:45 AM
10.82.8.239 Ping Dec 01 2021 12:45 AM
10.82.8.231 Ping Dec 01 2021 12:45 AM
10.82.8.228 Ping Dec 01 2021 12:45 AM
10.82.8.241 Ping Dec 01 2021 12:45 AM

[kastamonu.university]

These IPs were not given to the devices manually.

[MHM Cisco World]

follow

[paul driver · Accepted solution]

Hello
What you are seeing is due to ip dhcp conflicts being enabled (by default) when the dhcp pool is created and activated

Before an ip allocation the server will send a ping for that ip and if it receives a rely it won’t allocate that ip  but will reserve it so it isn’t used,

When you do a sh ip dhcp confllcit that listing shows how many reply’s the server has had from its ping checks and then has registered as conflict, this ip listing will removed from the pool of available addresses in the dhcp scope < (Excluded addresses :xx)

To negate this, you can:

• Turn of dhcp conflict < no ip dhcp conflict logging
• Decrease the dhcp lease times so they are released at the end of the day
• Manually or script the clearing of the ip dhcp conflict table.<  clear ip dhcp conflict *

[kastamonu.university]

Thank you for your interest.