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12

Why don't you set the IP for that appliance explicitely: # The standard subnet subnet 10.0.0.0 netmask 255.255.255.0 { option domain-name "ourdomain.internal"; option routers 10.0.0.1; option domain-name-servers 10.0.0.2; range 10.0.0.10 10.0.0.49; range 10.0.0.51 10.0.0.246; } #has hardcoded ip, and dhcp should not use that in pool ...


8

Something like this: class "specialK" { match if substring (hardware, 1, 3) = 00:01:02; } subnet 10.0.0.0 netmask 255.255.255.0 { pool { range 10.0.0.16 10.0.0.32; allow members of "specialK"; } } hmm, is it supposed to be (hardware, 0, 2) or (.. 1, 3), test it out. :)


6

While product recommendations are off-topic for ServerFault and I expect your question to be closed by the community in short order, I can offer two suggestions: Limiting yourself to a GUI-based system is limiting your ability to implement the best solution for your situation. Perhaps a system with a GUI will work well, or perhaps not. In spite of the ...


6

As MadHatter mentioned in a comment, the leases file is periodically re-created to avoid this problem. While the period isn't mentioned in the documentation, discussions on the dhcp-users mailinglist indicates that it should be done once an hour, and I've checked the source code and found that this is correct. Unfortunately this isn't a configurable option. ...


5

You can use something like: class "ignored" { match if substring(hardware,1,4) = 00:02; } pool { deny members of "ignored"; range 192.168.172.100 192.168.172.149; }


5

It is not mentioned explicitly in the manpage, but setting lease time to -1 in any of the options you mention, default-lease-time -1; max-lease-time -1; is effectively disabling the expiry time of the leases, so their expiration will be effectively set "to infinity".


4

The name has changed in IPv6it is called now dhcp6.vendor-opts. In the dhcpd6.conf file in the host section you must add: option dhcp6.vendor-opts "options"; Depending on the client you must need to modify its config file to request it.


4

The lease expires when its expiration time arrives. ISC dhcpd does not remove the leases until it "needs" to (e.g. it ran out of IPs to assign, so now it will assign one from an expired lease). This is to support an often-overlooked feature of DHCP -- the DHCP server will DHCPOFFER a given client (MAC address) the same address it's used previously, even if ...


4

It should be as simple as doing something like this. host windows-matt-2 { option domain-name-servers 1.2.3.4; option domain-name "foo"; option routers 5.6.7.8; option broadcast-address 10.100.255.255; default-lease-time 600; max-lease-time 7200; hardware ethernet 00:1f:d0:a1:55:5d; fixed-address 10.100.101.21; } subnet 10.100.0.0 netmask ...


4

On my system (debian lenny), I need to need binary-to-ascii in order to match mac-addresses. In this (working) example from my dhcpd.conf, server247 is in class "local", however, I give it a fixed address that it not in the pool. I would recommend that the fixed addresses be in a separate range from the dynamically assigned addresses (they can still be in ...


4

No. Clients default to using the highest address in the subnet if a broadcast address is not specified. Remember to keep that address out of the dhcp pool.


4

DHCP protocol uses 67 and 68 port numbers. dhcpd cannot out of the blue start listening on port 80 'because it is free'. And one more thing, using t option in netstat you lists only TCP protocol. How come you see dhcp server which is using UDP protocol ? You have probably misread netstat output.


3

This rather old wiki post indicates that Mac OS X does send a VCI of AAPLBSDPC plus some other info about the processor and machine type back to the server. However, I'm not having any luck finding any info on how you would actually change that value on the client. I think your only option may be to run a different client.


3

So i havn't done this with option 82, but your best bet would be to use classing in isc dhcpd. What you would do is setup a class like: class "userclass1" { match if substring(option agent.circuit-id, 2, 2) = "<your_id1>"; } class "userclass2" { match if substring(option agent.circuit-id, 2, 2) = "<your_id2>"; } Then in your pool ...


3

That's REALLY not how it works at all, there's zero reason why any form of upstream routing issue or misconfiguration would lead to a DHCP problem. Maybe if you were like a home user or a two-man business using the cheapest of DSL router then perhaps I could see why it may cause problems but in any other scenario these two things have no impact on each ...


3

Not how it works on my end. Is the info that the server is pushing possibly pointing to an external resource that is vanished due to the lack of internet at the time DHCP is trying to serve the request? Example, is the gateway that you are pushing, reachable when the network is down? How about DNS server being pushed?


3

Yes, you can set options based on conditional statements in the ISC dhcpd server. Specifically you can test if the dhcp-client-identifier option is present in the incoming DHCP packet, and if it is set the option for the response packet to the incoming value by this expression: # other options in scope ... if exists dhcp-client-identifier { option ...


3

The configuration checker would just match your defined pools and host address definitions against each other to find definition intersections, it would not evaluate access lists. So you would have to explicitly exclude your host definitions range from the "deny all" pool definition: pool { # IP range which will be assigned statically range ...


3

Since the three subnets share the same medium (eth2), they should be declared inside the same shared-network: shared-network my-net { subnet 10.1.1.0 netmask 255.255.255.0 { ... } subnet 10.1.2.0 netmask 255.255.255.0 { ... } subnet 10.1.3.0 netmask 255.255.255.0 { ... } }


3

Why not specify a tftp server that's a hop away? As long as your clients are receiving the appropriate default gateway this might be the easiest way to go. That said, if you must support multiple interfaces - It's possible to run multiple instances of dhcpd. Each would have its own configuration that would include entries to specifically bind said ...


3

You might look at building a custom iPXE image with an embedded ipxe script that chainloads whatever you want to see after netbooting (e.g., menu.c32, vesamenu.c32, pxelinux, etc.). The nice thing is that iPXE doesn't need any passed DHCP options at all (e.g., options 66 and 67). What's embedded in the ipxe script will be used instead. It just needs DHCP ...


3

It goes: CLIENT -> DHCPDISCOVER SERVER -> DHCPOFFER CLIENT -> DHCPREQUEST SERVER -> DHCPACK You you are missing the DHCPREQUEST before the DHCPACK in your description. If the client is on a different subnet than the DHCP server the DHCPOFFER is sent unicast to the DHCP-relay on port 67 UDP. The DHCP-relay agent broadcasts the DHCPOFFER to the ...


3

You should not configure an infinite lease time. The reason of having DHCP is to have a central management and flexibility. Making the lease time infinite, you will kill the flexibility.


3

ISC DHCP certainly will request a prefix delegation from your ISP if you ask it to, but it won't actually do anything with it beyond logging it somewhere. Nor will any other DHCP client. If you really intend to build your own router, you'll have to write your own scripts to determine the prefix that was delegated, set up static routes, and configure your ...


2

dhcpcd after 6.4.0 (or fetch the trunk from the repository) will request and disposition a ia-pd prefix. for instance the nominal config interface eth1 ia-pd 1/::/60 eth2/2/64 eth3/3/64 will request a prefix with a length of 60 (so four bits, a.k.a. eight networks) and assign the resulting networks to the listed interfaces, with the prefix length ...


2

Create an empty declaration for your 10.4.1.0/24 network. subnet 10.4.1.0 netmask 255.255.255.0 { } And don't use that deprecated alias nonsense for multiple addresses. You don't need it, and it just confuses things. Setup your interfaces file like this. This results in the same effective configuration if you look at it using ip addr. and ip route. ...


2

Use ebtables instead of iptables to block MAC addresses at layer 2: ebtables -A INPUT -s 00:11:22:33:44:55 -j DROP


2

You can't control somebody else's computer. If somebody else has "Administrator" or superuser-level access to the machine then all bets are off. You're better off doing this in the network, where you can control things. I see you say "...without the help of the router", but enforcing network policy with the network equipment gives you the best chance to a ...


2

You will need to either tell the default gateway on the network eth2 is connected to that 10.0.0.0/24 is behind that router by specifying a default route (i.e. on your cable modem which is apparently acting as a router also), or use source NAT on traffic outbound on eth2. Double NAT is inadvisable and so if you are doing that you should find some way to get ...



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