Dear Sir/Madam, I finally got to the core of the problems with dhclient.conf, documentation etc. Everything was cause by the 'send user-class "some-user-class"' entry in the dhclient.conf file. It appears that according to the RFC 3004 one needs to have the user-class string entered as "\017some-user-class". It would well support and m-array of user classes in this option. It would be neat though to have that documented. Without the length-meaning non-printable characters I was experiencing the 'malformed' packets emitted by the client. The dhclient version in use 4.4.1. With my best wishes Tomasz Motyl -----Original Message----- From: DHCP Public Bugs via RT [mailto:dhcp-public@isc.org] Sent: 07 December 2018 00:36 To: Tomasz Motyl Subject: [ISC-Bugs #48604] AutoReply: The dhclient.conf problems... 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The documentation is extremely vague in that area and I believe that number of examples (man pages provide us with only one) would be of extreme benefit. Actually trivial thing from the perspective of the protocol - option 60 to be sent by the client in the DHCP request packet. I strongly encourage you to try googling it... I daresay would be faster writing the packet in the hex editor and push it raw to the wire than figure out how to do this reading the man-pages. Yes this is that bad. With my best wishes Tomasz Motyl ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. ______________________________________________________________________