00:02:48 dhcpd: uid lease 192.168.3.104 for client 00:11:32:8e:aa:b7 is duplicate on 192.168.3.0 /24
I cannot find the IP 192.168.3.104.
All network nodes are set to DHCP.
The IP is also not listed on the DHCP configuration page.
With Ping it is also not reachable.
The MAC address 00:11:32:8e:aa:b7 belongs to the IP 192.168.3.81 (DHCP).
This is listed.
The connected server is a small Synology DS216es.
A second one with the same configuration did not show any problems.
all participants in green and blue are set to a fixed IP by DHCP.
the DHCP IP address range is limited to a single address. green 192.168.2.250 and blue 192.168.3.250
Why some devices want to have a 2nd IP is still unknown to me.
Affected are Win10, Win7, Fritzbox(Lan1) and Synology server.
The other network participants e.g. Ubuntuserver, BMZ… do not do that.
I have attached the log list, if anyone is interested.
10:39:20 dhcpd: uid lease 192.168.3.103 for client bc:05:43:6b:9c:4b is duplicate on 192.168.3.0/24
10:39:20 dhcpd: DHCPREQUEST for 192.168.3.80 from bc:05:43:6b:9c:4b via blue0
10:39:20 dhcpd: DHCPACK on 192.168.3.80 to bc:05:43:6b:9c:4b via blue0
10:39:48 dhcpd: DHCPREQUEST for 192.168.2.51 from 00:24:5b:00:06:15 via green0
10:39:48 dhcpd: DHCPACK on 192.168.2.51 to 00:24:5b:00:06:15 via green0
10:40:49 dhcpd: uid lease 192.168.2.101 for client 2c:56:dc:77:8b:46 is duplicate on 192.168.2.0/24
10:40:49 dhcpd: DHCPREQUEST for 192.168.2.21 from 2c:56:dc:77:8b:46 via green0
10:40:49 dhcpd: DHCPACK on 192.168.2.21 to 2c:56:dc:77:8b:46 via green0
10:41:33 dhcpd: DHCPREQUEST for 192.168.2.56 from 00:15:99:67:d5:cd via green0
10:41:33 dhcpd: DHCPACK on 192.168.2.56 to 00:15:99:67:d5:cd via green0
10:41:58 dhcpd: uid lease 192.168.2.100 for client 90:fb:a6:30:88:55 is duplicate on 192.168.2.0/24
10:41:58 dhcpd: DHCPREQUEST for 192.168.2.20 from 90:fb:a6:30:88:55 via green0
10:41:58 dhcpd: DHCPACK on 192.168.2.20 to 90:fb:a6:30:88:55 via green0
10:43:13 dhcpd: DHCPREQUEST for 192.168.3.82 from 1c:87:76:b0:30:5f via blue0
10:43:13 dhcpd: DHCPACK on 192.168.3.82 to 1c:87:76:b0:30:5f via blue0
10:43:34 dhcpd: uid lease 192.168.3.104 for client 00:11:32:8e:aa:b7 is duplicate on 192.168.3.0/24
10:43:34 dhcpd: DHCPREQUEST for 192.168.3.81 from 00:11:32:8e:aa:b7 via blue0
10:43:34 dhcpd: DHCPACK on 192.168.3.81 to 00:11:32:8e:aa:b7 via blue0
10:43:38 dhcpd: DHCPREQUEST for 192.168.2.83 from 90:2b:34:55:d3:2c via green0
10:43:38 dhcpd: DHCPACK on 192.168.2.83 to 90:2b:34:55:d3:2c via green0
10:43:44 dhcpd: DHCPREQUEST for 192.168.2.50 from e0:cb:4e:1f:98:1e via green0
10:43:44 dhcpd: DHCPACK on 192.168.2.50 to e0:cb:4e:1f:98:1e via green0
10:44:20 dhcpd: uid lease 192.168.3.103 for client bc:05:43:6b:9c:4b is duplicate on 192.168.3.0/24
10:44:20 dhcpd: DHCPREQUEST for 192.168.3.80 from bc:05:43:6b:9c:4b via blue0
10:44:20 dhcpd: DHCPACK on 192.168.3.80 to bc:05:43:6b:9c:4b via blue0
10:44:48 dhcpd: DHCPREQUEST for 192.168.2.51 from 00:24:5b:00:06:15 via green0
10:44:48 dhcpd: DHCPACK on 192.168.2.51 to 00:24:5b:00:06:15 via green0
10:45:49 dhcpd: uid lease 192.168.2.101 for client 2c:56:dc:77:8b:46 is duplicate on 192.168.2.0/24
10:45:49 dhcpd: DHCPREQUEST for 192.168.2.21 from 2c:56:dc:77:8b:46 via green0
10:45:49 dhcpd: DHCPACK on 192.168.2.21 to 2c:56:dc:77:8b:46 via green0
10:46:11 dhcpd: lease 192.168.3.102: no subnet.
10:46:11 dhcpd: lease 192.168.3.100: no subnet.
10:46:11 dhcpd: lease 192.168.3.104: no subnet.
10:46:11 dhcpd: lease 192.168.3.103: no subnet.
10:46:11 dhcpd: lease 192.168.3.101: no subnet.
10:46:11 dhcpd: lease 192.168.3.105: no subnet.
10:46:11 dhcpd: Wrote 0 deleted host decls to leases file.
10:46:11 dhcpd: Wrote 0 new dynamic host decls to leases file.
10:46:11 dhcpd: Wrote 7 leases to leases file.
10:46:11 dhcpd: Server starting service.
10:46:35 dhcpd: DHCPREQUEST for 192.168.2.56 from 00:15:99:67:d5:cd via green0
10:46:35 dhcpd: DHCPACK on 192.168.2.56 to 00:15:99:67:d5:cd via green0
10:46:58 dhcpd: uid lease 192.168.2.100 for client 90:fb:a6:30:88:55 is duplicate on 192.168.2.0/24
10:46:58 dhcpd: DHCPREQUEST for 192.168.2.20 from 90:fb:a6:30:88:55 via green0
10:46:58 dhcpd: DHCPACK on 192.168.2.20 to 90:fb:a6:30:88:55 via green0
10:47:44 dhcpd: DHCPREQUEST for 192.168.3.81 from 00:11:32:8e:aa:b7 via blue0
10:47:44 dhcpd: DHCPACK on 192.168.3.81 to 00:11:32:8e:aa:b7 via blue0
10:48:00 dhcpd: DHCPREQUEST for 192.168.3.82 from 1c:87:76:b0:30:5f via blue0
10:48:00 dhcpd: DHCPACK on 192.168.3.82 to 1c:87:76:b0:30:5f via blue0
10:48:37 dhcpd: DHCPREQUEST for 192.168.2.83 from 90:2b:34:55:d3:2c via green0
10:48:37 dhcpd: DHCPACK on 192.168.2.83 to 90:2b:34:55:d3:2c via green0
10:48:45 dhcpd: DHCPREQUEST for 192.168.2.50 from e0:cb:4e:1f:98:1e via green0
10:48:45 dhcpd: DHCPACK on 192.168.2.50 to e0:cb:4e:1f:98:1e via green0
10:49:20 dhcpd: DHCPREQUEST for 192.168.3.80 from bc:05:43:6b:9c:4b via blue0
10:49:20 dhcpd: DHCPACK on 192.168.3.80 to bc:05:43:6b:9c:4b via blue0
10:49:49 dhcpd: DHCPREQUEST for 192.168.2.51 from 00:24:5b:00:06:15 via green0
10:49:49 dhcpd: DHCPACK on 192.168.2.51 to 00:24:5b:00:06:15 via green0
10:50:50 dhcpd: uid lease 192.168.2.101 for client 2c:56:dc:77:8b:46 is duplicate on 192.168.2.0/24
10:50:50 dhcpd: DHCPREQUEST for 192.168.2.21 from 2c:56:dc:77:8b:46 via green0
10:50:50 dhcpd: DHCPACK on 192.168.2.21 to 2c:56:dc:77:8b:46 via green0
10:51:37 dhcpd: DHCPREQUEST for 192.168.2.56 from 00:15:99:67:d5:cd via green0
10:51:37 dhcpd: DHCPACK on 192.168.2.56 to 00:15:99:67:d5:cd via green0
10:51:58 dhcpd: uid lease 192.168.2.100 for client 90:fb:a6:30:88:55 is duplicate on 192.168.2.0/24
10:51:58 dhcpd: DHCPREQUEST for 192.168.2.20 from 90:fb:a6:30:88:55 via green0
10:51:58 dhcpd: DHCPACK on 192.168.2.20 to 90:fb:a6:30:88:55 via green0
10:52:30 dhcpd: DHCPREQUEST for 192.168.3.82 from 1c:87:76:b0:30:5f via blue0
10:52:30 dhcpd: DHCPACK on 192.168.3.82 to 1c:87:76:b0:30:5f via blue0
10:52:43 dhcpd: DHCPREQUEST for 192.168.3.81 from 00:11:32:8e:aa:b7 via blue0
10:52:43 dhcpd: DHCPACK on 192.168.3.81 to 00:11:32:8e:aa:b7 via blue0
10:53:38 dhcpd: DHCPREQUEST for 192.168.2.83 from 90:2b:34:55:d3:2c via green0
10:53:38 dhcpd: DHCPACK on 192.168.2.83 to 90:2b:34:55:d3:2c via green0
10:53:45 dhcpd: DHCPREQUEST for 192.168.2.50 from e0:cb:4e:1f:98:1e via green0
10:53:45 dhcpd: DHCPACK on 192.168.2.50 to e0:cb:4e:1f:98:1e via green0
10:54:20 dhcpd: DHCPREQUEST for 192.168.3.80 from bc:05:43:6b:9c:4b via blue0
10:54:20 dhcpd: DHCPACK on 192.168.3.80 to bc:05:43:6b:9c:4b via blue0
10:54:20 dhcpd: uid lease 192.168.2.101 for client 2c:56:dc:77:8b:46 is duplicate on 192.168.2.0/24
10:54:20 dhcpd: DHCPREQUEST for 192.168.2.21 from 2c:56:dc:77:8b:46 via green0
10:54:20 dhcpd: DHCPACK on 192.168.2.21 to 2c:56:dc:77:8b:46 via green0
10:54:49 dhcpd: DHCPREQUEST for 192.168.2.51 from 00:24:5b:00:06:15 via green0
10:54:49 dhcpd: DHCPACK on 192.168.2.51 to 00:24:5b:00:06:15 via green0
10:56:35 dhcpd: DHCPREQUEST for 192.168.3.82 from 1c:87:76:b0:30:5f via blue0
10:56:35 dhcpd: DHCPACK on 192.168.3.82 to 1c:87:76:b0:30:5f via blue0
10:56:39 dhcpd: DHCPREQUEST for 192.168.2.56 from 00:15:99:67:d5:cd via green0
10:56:39 dhcpd: DHCPACK on 192.168.2.56 to 00:15:99:67:d5:cd via green0
10:56:56 dhcpd: lease 192.168.2.104: no subnet.
10:56:56 dhcpd: lease 192.168.2.100: no subnet.
10:56:56 dhcpd: lease 192.168.2.101: no subnet.
10:56:56 dhcpd: lease 192.168.2.103: no subnet.
10:56:56 dhcpd: lease 192.168.2.105: no subnet.
10:56:56 dhcpd: lease 192.168.2.106: no subnet.
10:56:56 dhcpd: lease 192.168.2.102: no subnet.
10:56:56 dhcpd: Wrote 0 deleted host decls to leases file.
10:56:56 dhcpd: Wrote 0 new dynamic host decls to leases file.
10:56:56 dhcpd: Wrote 0 leases to leases file.
10:56:56 dhcpd: Server starting service.
10:56:58 dhcpd: DHCPREQUEST for 192.168.2.20 from 90:fb:a6:30:88:55 via green0
10:56:58 dhcpd: DHCPACK on 192.168.2.20 to 90:fb:a6:30:88:55 via green0
10:57:03 dhcpd: DHCPINFORM from 192.168.2.20 via green0
10:57:03 dhcpd: DHCPACK to 192.168.2.20 (90:fb:a6:30:88:55) via green0
10:57:34 dhcpd: DHCPREQUEST for 192.168.3.81 from 00:11:32:8e:aa:b7 via blue0
10:57:34 dhcpd: DHCPACK on 192.168.3.81 to 00:11:32:8e:aa:b7 via blue0
10:58:37 dhcpd: DHCPREQUEST for 192.168.2.83 from 90:2b:34:55:d3:2c via green0
10:58:37 dhcpd: DHCPACK on 192.168.2.83 to 90:2b:34:55:d3:2c via green0
10:58:44 dhcpd: DHCPREQUEST for 192.168.2.50 from e0:cb:4e:1f:98:1e via green0
10:58:44 dhcpd: DHCPACK on 192.168.2.50 to e0:cb:4e:1f:98:1e via green0
10:59:19 dhcpd: DHCPREQUEST for 192.168.2.21 from 2c:56:dc:77:8b:46 via green0
10:59:19 dhcpd: DHCPACK on 192.168.2.21 to 2c:56:dc:77:8b:46 via green0
10:59:20 dhcpd: DHCPREQUEST for 192.168.3.80 from bc:05:43:6b:9c:4b via blue0
10:59:20 dhcpd: DHCPACK on 192.168.3.80 to bc:05:43:6b:9c:4b via blue0
10:59:50 dhcpd: DHCPREQUEST for 192.168.2.51 from 00:24:5b:00:06:15 via green0
10:59:50 dhcpd: DHCPACK on 192.168.2.51 to 00:24:5b:00:06:15 via green0
11:00:48 dhcpd: DHCPREQUEST for 192.168.3.82 from 1c:87:76:b0:30:5f via blue0
11:00:48 dhcpd: DHCPACK on 192.168.3.82 to 1c:87:76:b0:30:5f via blue0
11:01:41 dhcpd: DHCPREQUEST for 192.168.2.56 from 00:15:99:67:d5:cd via green0
11:01:41 dhcpd: DHCPACK on 192.168.2.56 to 00:15:99:67:d5:cd via green0
11:01:44 dhcpd: DHCPREQUEST for 192.168.3.81 from 00:11:32:8e:aa:b7 via blue0
11:01:44 dhcpd: DHCPACK on 192.168.3.81 to 00:11:32:8e:aa:b7 via blue0
11:01:58 dhcpd: DHCPREQUEST for 192.168.2.20 from 90:fb:a6:30:88:55 via green0
11:01:58 dhcpd: DHCPACK on 192.168.2.20 to 90:fb:a6:30:88:55 via green0
Were the clients connected by dynamic IPs in the beginning?
Then the DHCP server keeps these leases. Don’t know why they aren’t deleted. Maybe it is because of the basic functionality of the server. Dynamic leases are the main ‘product’. Our fixed leases are a special case.
The general processing of the ISC dhcpd is:
get request for a MAC
is the MAC known, either by a previous ( dynamic ) lease or a host definition ?
if yes, check for availability ( no client answers to a ping for ththe associated IP or host definition); if available hand over the associated IP
otherwise select the oldest lease and check ( step 3. )
I think because of step 4. dhcpcd doesn’t ‘forget’ those old leases. The messages about double definitions can be neglected.
I thought so too, but when I had the PCs only on DHCP without fixed assignment, the duplicates were always behind the DHCP assigned but in the DHCP range.
The more PCs logged on the further the duplicates moved to the back.
Somehow this was dynamic, as if someone absolutely needs a 2nd IP and gets none.