Closed
Description
Basic Infos
- This issue complies with the issue POLICY doc.
- I have read the documentation at readthedocs and the issue is not addressed there.
- I have tested that the issue is present in current master branch (aka latest git).
- I have searched the issue tracker for a similar issue.
- If there is a stack dump, I have decoded it.
- I have filled out all fields below.
Platform
- Hardware: [ESP-01|Wemos D1 mini R2]
- Core Version: [09c4e33]
- Development Env: [Arduino IDE]
- Operating System: [Windows|MacOS]
Settings in IDE
- Module: [Generic ESP8266 Module|Wemos D1 mini r2]
- Flash Mode: [DOUT]
- Flash Size: [1MB|4MB]
- lwip Variant: [v2 Lower Memory|v2 Higher Bandwidth]
- Reset Method: [dtr]
- Flash Frequency: [40Mhz]
- CPU Frequency: [80Mhz]
- Upload Using: [SERIAL]
- Upload Speed: [115200] (serial upload only)
Problem Description
The ESP8266 is not sending the Client Identifier when it request a DHCP server.
Some routers-gateway-dhcp require this option to register the ESP's hostname into their DNS.
On devices with several network interfaces it prevents the DHCP to assign an new address per interface.
Can we amend the Client Identifier (option 61) to the DHCP query?
MCVE Sketch
// cf https://github.com/esp8266/Arduino/blob/master/libraries/ESP8266mDNS/examples/mDNS_Web_Server/mDNS_Web_Server.inoDebug Messages
me@ime /Users/me sudo dhcpdump -i en0
TIME: 2021-07-18 00:30:26.692
IP: 0.0.0.0 (b4:e6:2d:ZZ:ZZ:ZZ) > 255.255.255.255 (ff:ff:ff:ff:ff:ff)
OP: 1 (BOOTPREQUEST)
HTYPE: 1 (Ethernet)
HLEN: 6
HOPS: 0
XID: 51fcZZZZ
SECS: 0
FLAGS: 0
CIADDR: 0.0.0.0
YIADDR: 0.0.0.0
SIADDR: 0.0.0.0
GIADDR: 0.0.0.0
CHADDR: b4:e6:2d:ZZ:ZZ:ZZ:00:00:00:00:00:00:00:00:00:00
SNAME: .
FNAME: .
OPTION: 53 ( 1) DHCP message type 1 (DHCPDISCOVER)
OPTION: 57 ( 2) Maximum DHCP message size 1500
OPTION: 55 ( 5) Parameter Request List 1 (Subnet mask)
3 (Routers)
28 (Broadcast address)
6 (DNS server)
42 (NTP servers)
---------------------------------------------------------------------------
TIME: 2021-07-18 00:30:26.794
IP: 0.0.0.0 (b4:e6:2d:ZZ:ZZ:ZZ) > 255.255.255.255 (ff:ff:ff:ff:ff:ff)
OP: 1 (BOOTPREQUEST)
HTYPE: 1 (Ethernet)
HLEN: 6
HOPS: 0
XID: 51fcZZZZ
SECS: 0
FLAGS: 0
CIADDR: 0.0.0.0
YIADDR: 0.0.0.0
SIADDR: 0.0.0.0
GIADDR: 0.0.0.0
CHADDR: b4:e6:2d:ZZ:ZZ:ZZ:00:00:00:00:00:00:00:00:00:00
SNAME: .
FNAME: .
OPTION: 53 ( 1) DHCP message type 3 (DHCPREQUEST)
OPTION: 57 ( 2) Maximum DHCP message size 1500
OPTION: 50 ( 4) Request IP address 192.168.1.20
OPTION: 54 ( 4) Server identifier 192.168.1.254
OPTION: 55 ( 5) Parameter Request List 1 (Subnet mask)
3 (Routers)
28 (Broadcast address)
6 (DNS server)
42 (NTP servers)
OPTION: 12 ( 10) Host name ESP-ZZZZZZ
---------------------------------------------------------------------------
VERSUS a right DHCP request:
me@ime /Users/me sudo dhcpdump -i en0
TIME: 2021-07-18 00:36:27.113
IP: 0.0.0.0 (98:1:a7:ZZ:ZZ:ZZ) > 255.255.255.255 (ff:ff:ff:ff:ff:ff)
OP: 1 (BOOTPREQUEST)
HTYPE: 1 (Ethernet)
HLEN: 6
HOPS: 0
XID: 7519ZZZZ
SECS: 0
FLAGS: 0
CIADDR: 0.0.0.0
YIADDR: 0.0.0.0
SIADDR: 0.0.0.0
GIADDR: 0.0.0.0
CHADDR: 98:01:a7:ZZ:ZZ:ZZ:00:00:00:00:00:00:00:00:00:00
SNAME: .
FNAME: .
OPTION: 53 ( 1) DHCP message type 3 (DHCPREQUEST)
OPTION: 55 ( 11) Parameter Request List 1 (Subnet mask)
121 (Classless Static Route)
3 (Routers)
6 (DNS server)
15 (Domainname)
114 (URL)
119 (Domain Search)
252 (MSFT - WinSock Proxy Auto Detect)
95 (LDAP)
44 (NetBIOS name server)
46 (NetBIOS node type)
OPTION: 57 ( 2) Maximum DHCP message size 1500
OPTION: 61 ( 7) Client-identifier 01:98:01:a7:ZZ:ZZ:ZZ
OPTION: 50 ( 4) Request IP address 192.168.1.11
OPTION: 51 ( 4) IP address leasetime 7776000 (12w6d)
OPTION: 12 ( 3) Host name iMe
---------------------------------------------------------------------------
TIME: 2021-07-18 00:36:28.529
IP: 0.0.0.0 (98:1:a7:ZZ:ZZ:ZZ) > 255.255.255.255 (ff:ff:ff:ff:ff:ff)
OP: 1 (BOOTPREQUEST)
HTYPE: 1 (Ethernet)
HLEN: 6
HOPS: 0
XID: 7519ZZZZ
SECS: 1
FLAGS: 0
CIADDR: 0.0.0.0
YIADDR: 0.0.0.0
SIADDR: 0.0.0.0
GIADDR: 0.0.0.0
CHADDR: 98:01:a7:ZZ:ZZ:ZZ:00:00:00:00:00:00:00:00:00:00
SNAME: .
FNAME: .
OPTION: 53 ( 1) DHCP message type 3 (DHCPREQUEST)
OPTION: 55 ( 11) Parameter Request List 1 (Subnet mask)
121 (Classless Static Route)
3 (Routers)
6 (DNS server)
15 (Domainname)
114 (URL)
119 (Domain Search)
252 (MSFT - WinSock Proxy Auto Detect)
95 (LDAP)
44 (NetBIOS name server)
46 (NetBIOS node type)
OPTION: 57 ( 2) Maximum DHCP message size 1500
OPTION: 61 ( 7) Client-identifier 01:98:01:a7:ZZ:ZZ:ZZ
OPTION: 50 ( 4) Request IP address 192.168.1.11
OPTION: 51 ( 4) IP address leasetime 7776000 (12w6d)
OPTION: 12 ( 3) Host name iMe
---------------------------------------------------------------------------
TIME: 2021-07-18 00:36:28.634
IP: 192.168.1.254 (0:24:d4:ZZ:ZZ:ZZ) > 192.168.1.11 (98:1:a7:ZZ:ZZ:ZZ)
OP: 2 (BOOTPREPLY)
HTYPE: 1 (Ethernet)
HLEN: 6
HOPS: 0
XID: 75198106
SECS: 0
FLAGS: 0
CIADDR: 0.0.0.0
YIADDR: 192.168.1.11
SIADDR: 0.0.0.0
GIADDR: 0.0.0.0
CHADDR: 98:01:a7:ZZ:ZZ:ZZ:00:00:00:00:00:00:00:00:00:00
SNAME: .
FNAME: .
OPTION: 53 ( 1) DHCP message type 5 (DHCPACK)
OPTION: 54 ( 4) Server identifier 192.168.1.254
OPTION: 51 ( 4) IP address leasetime 864000 (1w3d)
OPTION: 1 ( 4) Subnet mask 255.255.255.0
OPTION: 3 ( 4) Routers 192.168.1.254
OPTION: 6 ( 8) DNS server 212.27.888.888,212.27.888.888
---------------------------------------------------------------------------As you can see, the default Client Identifier is:
OPTION: 61 ( 7) Client-identifier 01:{{macAddress}}
And the field should be optional:
https://datatracker.ietf.org/doc/html/rfc4361