Questions[dhclient](ubuntu)

As the title says, when on eduroam my internet connection drops after some time (usually after a couple of minutes when I have a lot of traffic, e.g. zoom meetings, when there is less traffic it might hold for an hour). The laptop stays connected to the wifi but no website is accessible and I also can't ping any DNS servers (though existing connections with e.g. Netflix sometimes still work). I don't have this issue on Windows.

The journalctl output while when this happens is

Sep 02 22:40:19 carlos-linux wpa_supplicant[1062]: wlo1: SME: Trying to authenticate with f0:9e:63:05:60:71 (SSID='eduroam' freq=2412 MHz)
Sep 02 22:40:19 carlos-linux kernel: wlo1: disconnect from AP 34:6f:90:34:24:8e for new auth to f0:9e:63:05:60:71
Sep 02 22:40:19 carlos-linux kernel: wlo1: authenticate with f0:9e:63:05:60:71
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.1322] device (wlo1): supplicant interface state: completed -> authenticating
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.1323] device (p2p-dev-wlo1): supplicant management interface state: completed -> authenticating
Sep 02 22:40:19 carlos-linux kernel: wlo1: send auth to f0:9e:63:05:60:71 (try 1/3)
Sep 02 22:40:19 carlos-linux wpa_supplicant[1062]: wlo1: Trying to associate with f0:9e:63:05:60:71 (SSID='eduroam' freq=2412 MHz)
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.1582] device (wlo1): supplicant interface state: authenticating -> associating
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.1582] device (p2p-dev-wlo1): supplicant management interface state: authenticating -> associating
Sep 02 22:40:19 carlos-linux kernel: wlo1: authenticated
Sep 02 22:40:19 carlos-linux kernel: wlo1: associate with f0:9e:63:05:60:71 (try 1/3)
Sep 02 22:40:19 carlos-linux kernel: wlo1: RX ReassocResp from f0:9e:63:05:60:71 (capab=0x421 status=17 aid=0)
Sep 02 22:40:19 carlos-linux kernel: wlo1: f0:9e:63:05:60:71 denied association (code=17)
Sep 02 22:40:19 carlos-linux wpa_supplicant[1062]: wlo1: CTRL-EVENT-ASSOC-REJECT bssid=f0:9e:63:05:60:71 status_code=17
Sep 02 22:40:19 carlos-linux wpa_supplicant[1062]: wlo1: SME: Deauth request to the driver failed
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.2197] device (wlo1): supplicant interface state: associating -> disconnected
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.2198] device (p2p-dev-wlo1): supplicant management interface state: associating -> disconnected
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.3201] device (wlo1): supplicant interface state: disconnected -> scanning
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.3202] device (p2p-dev-wlo1): supplicant management interface state: disconnected -> scanning
Sep 02 22:40:19 carlos-linux wpa_supplicant[1062]: wlo1: SME: Trying to authenticate with 34:6f:90:34:24:8e (SSID='eduroam' freq=5240 MHz)
Sep 02 22:40:19 carlos-linux kernel: wlo1: authenticate with 34:6f:90:34:24:8e
Sep 02 22:40:19 carlos-linux kernel: wlo1: send auth to 34:6f:90:34:24:8e (try 1/3)
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.4885] device (wlo1): supplicant interface state: scanning -> authenticating
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.4886] device (p2p-dev-wlo1): supplicant management interface state: scanning -> authenticating
Sep 02 22:40:19 carlos-linux wpa_supplicant[1062]: wlo1: Trying to associate with 34:6f:90:34:24:8e (SSID='eduroam' freq=5240 MHz)
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.5025] device (wlo1): supplicant interface state: authenticating -> associating
Sep 02 22:40:19 carlos-linux NetworkManager[1239]: <info>  [1599111619.5025] device (p2p-dev-wlo1): supplicant management interface state: authenticating -> associating
Sep 02 22:40:19 carlos-linux kernel: wlo1: authenticated
Sep 02 22:40:19 carlos-linux kernel: wlo1: associate with 34:6f:90:34:24:8e (try 1/3)
Sep 02 22:40:19 carlos-linux kernel: wlo1: RX AssocResp from 34:6f:90:34:24:8e (capab=0x101 status=30 aid=0)
Sep 02 22:40:19 carlos-linux kernel: wlo1: 34:6f:90:34:24:8e rejected association temporarily; comeback duration 1000 TU (1024 ms)
Sep 02 22:40:19 carlos-linux kernel: iwlwifi 0000:00:14.3: Unhandled alg: 0x707
Sep 02 22:40:19 carlos-linux kernel: iwlwifi 0000:00:14.3: Unhandled alg: 0x707
Sep 02 22:40:19 carlos-linux kernel: iwlwifi 0000:00:14.3: Unhandled alg: 0x707
Sep 02 22:40:19 carlos-linux kernel: iwlwifi 0000:00:14.3: Unhandled alg: 0x707
Sep 02 22:40:20 carlos-linux kernel: iwlwifi 0000:00:14.3: No beacon heard and the time event is over already...
Sep 02 22:40:20 carlos-linux kernel: wlo1: Connection to AP 34:6f:90:34:24:8e lost
Sep 02 22:40:20 carlos-linux kernel: wlo1: associate with 34:6f:90:34:24:8e (try 2/3)
Sep 02 22:40:20 carlos-linux kernel: wlo1: RX AssocResp from 34:6f:90:34:24:8e (capab=0x101 status=30 aid=0)
Sep 02 22:40:20 carlos-linux kernel: wlo1: 34:6f:90:34:24:8e rejected association temporarily; comeback duration 1000 TU (1024 ms)
Sep 02 22:40:20 carlos-linux kernel: iwlwifi 0000:00:14.3: Unhandled alg: 0x707
Sep 02 22:40:20 carlos-linux kernel: iwlwifi 0000:00:14.3: Unhandled alg: 0x707
Sep 02 22:40:21 carlos-linux kernel: iwlwifi 0000:00:14.3: No beacon heard and the time event is over already...
Sep 02 22:40:21 carlos-linux kernel: wlo1: Connection to AP 34:6f:90:34:24:8e lost
Sep 02 22:40:21 carlos-linux kernel: wlo1: associate with 34:6f:90:34:24:8e (try 3/3)
Sep 02 22:40:21 carlos-linux kernel: wlo1: RX AssocResp from 34:6f:90:34:24:8e (capab=0x1101 status=17 aid=0)
Sep 02 22:40:21 carlos-linux kernel: wlo1: 34:6f:90:34:24:8e denied association (code=17)
Sep 02 22:40:21 carlos-linux wpa_supplicant[1062]: wlo1: CTRL-EVENT-ASSOC-REJECT bssid=34:6f:90:34:24:8e status_code=17
Sep 02 22:40:21 carlos-linux wpa_supplicant[1062]: wlo1: SME: Deauth request to the driver failed
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.6374] device (wlo1): supplicant interface state: associating -> disconnected
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.6374] device (p2p-dev-wlo1): supplicant management interface state: associating -> disconnected
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.7377] device (wlo1): supplicant interface state: disconnected -> scanning
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.7378] device (p2p-dev-wlo1): supplicant management interface state: disconnected -> scanning
Sep 02 22:40:21 carlos-linux wpa_supplicant[1062]: wlo1: SME: Trying to authenticate with 34:6f:90:34:24:81 (SSID='eduroam' freq=2462 MHz)
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.8833] device (wlo1): supplicant interface state: scanning -> authenticating
Sep 02 22:40:21 carlos-linux kernel: wlo1: authenticate with 34:6f:90:34:24:81
Sep 02 22:40:21 carlos-linux kernel: wlo1: send auth to 34:6f:90:34:24:81 (try 1/3)
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.8834] device (p2p-dev-wlo1): supplicant management interface state: scanning -> authenticating
Sep 02 22:40:21 carlos-linux wpa_supplicant[1062]: wlo1: Trying to associate with 34:6f:90:34:24:81 (SSID='eduroam' freq=2462 MHz)
Sep 02 22:40:21 carlos-linux NetworkManager[1239]: <info>  [1599111621.9074] device (wlo1): supplicant interface state: authenticating -> associating
Sep 02 22:40:21 carlos-linux kernel: wlo1: authenticated

This is the same issue as described here, but the fix there does not work for me. I guess that's because my Ubuntu networking config is different from their Arch config, so if anyone can tell me what to change in my config to make it match Arch's ("default") config, I would also appreciate that.

Edit: The problem is caused by switching APs so fixing the BSSID for the network in Gnome's config fixes the disconnects, but this probably not optimal...

Edit 2: It seems that my wifi adapter is being recognized as Killer Wi-Fi 6 AX1650i 160MHz Wireless Network Adapter (201NGW) even though it's a intel AX201. I also found these lines in my dmesg:

[    4.382504] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-Qu-c0-hr-b0-56.ucode failed with error -2
[    4.387696] iwlwifi 0000:00:14.3: loaded firmware version 55.d9698065.0 Qu-c0-hr-b0-55.ucode op_mode iwlmvm
[    4.387716] iwlwifi 0000:00:14.3: Direct firmware load for iwl-debug-yoyo.bin failed with error -2

Does this mean that the wrong firmware is being loaded for the device?

Diagnostics:

• When this happens mtr says "no route to host"
• pgrep -a dh gives two entries:

995171 /sbin/dhclient -d -q -sf /usr/lib/NetworkManager/nm-dhcp-helper -pf /run/NetworkManager/dhclient-wlo1.pid -lf /var/lib/NetworkManager/dhclient-85e18157-cc78-4948-a5fb-300853e6bb8b-wlo1.lease -cf /var/lib/NetworkManager/dhclient-wlo1.conf wlo1

995228 /sbin/dhclient -d -q -6 -S -sf /usr/lib/NetworkManager/nm-dhcp-helper -pf /run/NetworkManager/dhclient6-wlo1.pid -lf /var/lib/NetworkManager/dhclient6-85e18157-cc78-4948-a5fb-300853e6bb8b-wlo1.lease -cf /var/lib/NetworkManager/dhclient6-wlo1.conf wlo1

When I try to use dhclient vpn_vpn it shows an error as below:

root@sunimali-HP-ProBook-450-G6:/home/sunimali# dhclient vpn_vpn
cmp: EOF on /tmp/tmp.EnmkqhupY9 which is empty
root@sunimali-HP-ProBook-450-G6:/home/sunimali# dhclient vpn_vpn
RTNETLINK answers: File exists
PING 172.16.0.8 (172.16.0.8) 56(84) bytes of data.

--- 172.16.0.8 ping statistics ---
1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms

sudo dhclient:

[sudo] password for sunimali: 
RTNETLINK answers: File exists
cmp: EOF on /tmp/tmp.qlfvdHMZt4 which is empty

sudo dhclient -v:

Internet Systems Consortium DHCP Client 4.4.1
Copyright 2004-2018 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/

Listening on LPF/vethb36997a/4a:d3:20:cf:d8:5d
Sending on   LPF/vethb36997a/4a:d3:20:cf:d8:5d
Listening on LPF/docker0/02:42:63:cb:90:be
Sending on   LPF/docker0/02:42:63:cb:90:be
Listening on LPF/br-c9556f64d33b/02:42:2a:da:f2:f6
Sending on   LPF/br-c9556f64d33b/02:42:2a:da:f2:f6
Listening on LPF/br-6aee2e92098e/02:42:3b:4f:9f:0b
Sending on   LPF/br-6aee2e92098e/02:42:3b:4f:9f:0b
Listening on LPF/wlp3s0/40:23:43:05:11:71
Sending on   LPF/wlp3s0/40:23:43:05:11:71
Listening on LPF/enp2s0/04:0e:3c:93:62:91
Sending on   LPF/enp2s0/04:0e:3c:93:62:91
Sending on   Socket/fallback
DHCPDISCOVER on vethb36997a to 255.255.255.255 port 67 interval 3 (xid=0x9d566d03)
DHCPDISCOVER on docker0 to 255.255.255.255 port 67 interval 3 (xid=0x6b72fd42)
DHCPDISCOVER on br-c9556f64d33b to 255.255.255.255 port 67 interval 3 (xid=0x5376d59)
DHCPDISCOVER on br-6aee2e92098e to 255.255.255.255 port 67 interval 3 (xid=0x4d04584f)
DHCPREQUEST for 192.168.8.100 on wlp3s0 to 255.255.255.255 port 67 (xid=0x7f5e15ca)
DHCPDISCOVER on enp2s0 to 255.255.255.255 port 67 interval 3 (xid=0x86040e7e)
DHCPACK of 192.168.8.100 from 192.168.8.1 (xid=0xca155e7f)
RTNETLINK answers: File exists
bound to 192.168.8.100 -- renewal in 40481 seconds.

I'm trying to figure out how to configure my DHCP client on Ubuntu server 18.04.

I have the following netplan configuration, coming from cloud-init:

network:
    version: 2
    ethernets:
        ens160:
            dhcp4: true
            match:
                macaddress: 02:dc:01:00:38:4c
            set-name: ens160

This seems to properly configure my network interface with an ip address, dns, default gateway and search domain. However, I'm wondering how to obtain a hostname from DHCP. I've been looking into dhclient which provides some convenient hooks that I can use, however it doesn't appear that dhclient hooks are being called. I've noticed that cloud-init calls dhclient as per the logs, but as some sort of sandboxed version, which seems to ignore the hooks.

I've also noticed that systemd-networkd reports some DHCP activity regarding to DHCP leases.

Could someone shed some light into the process?

I'm using Ubuntu 12.04 LTS, but I need to run the following command:

sudo dhclient

after startup to acquire a stable ethernet connection. I am running dhclient during startup already, through the /etc/rc.local file.

Someone please help me run this command after-startup automatically (by removing it's requirement for root, or some other means), or suggest a different way of troubleshooting my ethernet connection.

I have encountered a very weird error on ubuntu-server (8.04), I have no idea why dhclient is not allowed to set the network settings! I'm not the one who installed the server in the first place, so i don't know much about the setup. The server is only used as a firewall/gateway (custom iptables script) it's got three nic's one for internet, one for LAN and one for DMZ. Now the ISP have changed settings from static ip to "static" ip assigned through dhcp, and i cant really use it.

Sadly I can't just set the IP statically since the ISP closes my connection when the dhcp lease ends :o

This is the error i get: (and then it just hangs there..)

root@fw:~# dhclient eth2
Internet Systems Consortium DHCP Client V3.0.6
Copyright 2004-2007 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

SIOCSIFADDR: Permission denied
SIOCSIFFLAGS: Permission denied
SIOCSIFFLAGS: Permission denied
Listening on LPF/eth2/00:50:52:c1:a1:32
Sending on   LPF/eth2/00:50:52:c1:a1:32
Sending on   Socket/fallback
DHCPDISCOVER on eth2 to 255.255.255.255 port 67 interval 8
DHCPOFFER of 2.10.56.19 from 93.87.36.42
DHCPREQUEST of 2.10.56.19 on eth2 to 255.255.255.255 port 67
DHCPACK of 2.10.56.19 from 93.87.36.42
SIOCSIFADDR: Permission denied
SIOCSIFFLAGS: Permission denied
SIOCSIFNETMASK: Permission denied
SIOCSIFBRDADDR: Permission denied
SIOCSIFFLAGS: Permission denied
SIOCADDRT: Operation not permitted

for now i've fixed it by running killall dhclient; dhclient eth2 every hour and then setting static IP settings for the interface, this is enough to keep the connection live! but it's a pretty ugly hack in my opinion..