DHCP Problem /8er Netzwerk

Guten Tag,

Ich habe ein problem mit dem Dhcp server auf einem interface, das Netzt ist ein 2.0.0.1/8er netz. Mein Problem ist, dass die Adressen nicht nacheinander verteil werden also: 2.0.0.150 dann 2.0.0.151 usw.
Aktuell bekommt das nächste Device die Adresse 2.0.1.59 dann das nächste gerät die 2.0.1.14? Ist das ein bug? oder habe ich da einen fehler in meiner config?

@Spacelord09, welcome to the community!

Good day,

I have a problem with the Dhcp server on an interface that is a 2.0.0.1/8 network. My problem is that the addresses are not distributed one after the other: 2.0.0.150 then 2.0.0.151 etc.
Currently the next device gets the address 2.0.1.59 then the next device gets 2.0.1.14? Is this a bug? or do I have an error in my config?

  • Dieser IP-Bereich gehört Orange (französischer ISP). Ich rate davon ab, den öffentlichen IP-Adressraum zu verwenden.

That IP space is owned by Orange (French ISP), I advise not using Public IP address space.

  • Das A / 8-Subnetz ist ziemlich groß. Sind Sie sicher, dass Sie 16,7 Millionen Clients in Ihrem LAN benötigen?

A /8 subnet is quite huge, are you sure you need 16.7 million clients on your LAN?

  • Es gibt keinen Bug oder Fehler. Für nichts müssen IP-Adressen in aufsteigender Reihenfolge vergeben werden.

There is no bug or error. Nothing requires IPs to be issued in ascending sequential order.

Vielleicht möchten Sie verwenden:

You may wish to use

10.0.0.0/24

Nein ich benötige zwingend das 2.0.0.1/8er Netz. Dies ist komplett Privat mit keinerlei Verbindung ins Internet etc. Wie kommen diese Adressen zustande?

When writing in your native language, please always provide an english translation.
This way other users all around the world can take part in the discussion and possibly benefit from the outcome, without having to use a translator.

Thanks!

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Ok! I'll do that next time.

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  • I'm not sure why you wish to use Public IP space on an offline LAN; but OK - we can't stop you from numbering your network as you desire.
  • Also note that OpenWrt DHCP by default only issues 100 IPs; and the dnsmasq server has a default config max of 1000. Both settings can be increased, though.

If you're asking "why do I believe the Public IP space is owned by Orange S.A. of France"... because Regional Internet Registries (RIRs) issue Public IP space, the RIR that covers France is the The Réseaux IP Européens Network Coordination Centre. See:

By the way, again, there's no bug or error with the non-sequential DHCP leases.

Not a bug. dnsmasq gives out IP addresses based on the MAC address of the requesting host, or at least tries to. Which means that DHCP clients stay relatively stable on an address, and addresses are spread pseudorandomly over the whole DHCP range.

However, dnsmasq has an option --dhcp-sequential-ip reflected in

option sequential_ip 1

in /etc/config/dhcp which would prompt it to give out addresses in sequential order. At least in theory -- never needed it, never tried it, can't help you any further than point you to it

Edit: I would really like to reiterate what others already said: Other than "aesthetics" there is no benefit in giving out sequential addresses. If you choose to do that and forego the based-on-MAC default, expect having to look up a device's IP every time it reconnects because it may be different all the time.

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