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Am Tue, 21 Mar 2017 22:17:50 +0000 |
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schrieb Neil Bothwick <neil@××××××××××.uk>: |
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> On Tue, 21 Mar 2017 20:25:18 +0100, Kai Krakow wrote: |
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> |
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> > If it's systemd-networkd, you could check those logs after the |
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> > problem occurred: |
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> > |
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> > # journalctl -b -u systemd-networkd.service | fgrep -i dhcpv4 |
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> > |
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> > Apparently, it doesn't tell you what the DHCP server is by MAC |
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> > address, but the reported "via" at least tells you the IP. |
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> > |
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> > It looks like this: |
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> > |
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> > Mar 17 19:21:33 jupiter systemd-networkd[680]: enp5s0: DHCPv4 |
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> > address 192.168.4.102/24 via 192.168.4.254 |
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> |
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> That doesn't appear to be as helpful as you would think, I just tried |
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> it and got |
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> |
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> Mar 21 09:02:56 fenchurch systemd-networkd[495]: wlan0: DHCPv4 address |
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> 192.168.1.6/24 via 192.168.1.42 |
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> |
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> Which looks fine and 192.168.1.42 is the address of my router, but |
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> that router is not my DHCP server. I double checked and |
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> |
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> 1) DHCP is turned off on the router |
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> 2) The dnsmasq log on my DHCP server box shows it issuing that |
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> address at that time. |
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Ah, okay, so "via" announces the route. Good that we sorted that out |
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(and good to know) ;-) |
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Well, then fall back to tcpdump. You can filter it to DHCP traffic. You |
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can also use wireshark, it's a bit more easy to use as a beginner - |
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because it's graphical. |
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-- |
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Regards, |
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Kai |
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Replies to list-only preferred. |
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