Как отладить сервер, который не освобождает свой DHCP IP?

Как отладить сервер, который не освобождает свой DHCP IP?

Похоже, мой сервер продолжает запрашивать адрес DHCP, но не освобождает старые. Раньше он был напрямую подключен к моему провайдеру и удерживал тысячи аренд DHCP (это могло вызвать DoS по всему городу).

Сервер все еще может получить доступ к интернету. Проблема не вызывает проблем с подключением к серверу, но все остальные не могут использовать заявленные IP-адреса.

В попытке локализовать проблему я подключил его к локальной сети. Неудивительно, что это исчерпало пул IP-адресов маршрутизатора. Все IP-адреса были доступны с локального хоста (я могу пинговать его, задержка <1 мс), но не снаружи.

У меня нет большого опыта работы с dhclient, или с тем, как сервер обрабатывает получение/освобождение IP-адресов. /etc/network/interfacesне изменен, за исключениемallow-hotplug ens5

Проблема могла начаться, когда я

  • заменено sendmailна postfix( apt-get install postfix, ничего больше)
  • запустил apt-get upgrade(обновил ядро ​​и некоторые модули PHP, больше ничего)

У меня нет никаких пользовательских скриптов на сервере. dmesgчистый. Это веб-сервер, и большая часть того, что я делаю, находится либо на нем nginx, либо внутри сайта (Wordpress).

Как мне вообще начать отлаживать это? Я с таким раньше не сталкивался.

root@placeholder-not-actual-hostname:~# uname -a
Linux placeholder-not-actual-hostname 4.9.0-5-amd64 #1 SMP Debian 4.9.65-3+deb9u2 (2018-01-04) x86_64 GNU/Linux

Вывод ip a:

root@placeholder-not-actual-hostname:~# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: ens5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether e0:cb:4e:48:4e:28 brd ff:ff:ff:ff:ff:ff
    inet 192.168.249.2/24 brd 255.255.255.255 scope global ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.3/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.4/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.5/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.6/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.7/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.8/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.9/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.10/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.11/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.12/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.13/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.14/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.15/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.16/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.17/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.18/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.19/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.20/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.21/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.22/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.23/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.24/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.25/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.26/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.27/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.28/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.29/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.30/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.31/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.32/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.33/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.34/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.35/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.36/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.37/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.38/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.39/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.40/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.41/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.42/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.43/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.44/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.45/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.46/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.47/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.48/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.49/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.50/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.51/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.52/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.53/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.54/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.55/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.56/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.57/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.58/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.59/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.60/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.61/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.62/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.63/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.64/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.65/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.66/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.67/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.68/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.69/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.70/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.72/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.73/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.74/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.75/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.76/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.77/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.78/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.79/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.80/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.81/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.82/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.83/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.84/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.85/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.86/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.87/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.88/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.89/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.90/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.91/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.92/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.93/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.94/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.95/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.96/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.97/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.98/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.99/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.100/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.101/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.102/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.103/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.104/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.105/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.106/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.107/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.108/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.109/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.110/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.111/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.112/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.113/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.114/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.115/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.116/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.117/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.118/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.119/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.120/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.121/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.122/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.123/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.124/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.125/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.126/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.127/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.128/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.129/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.130/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.131/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.132/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.133/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.134/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.135/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.136/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.137/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.138/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.139/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.140/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.141/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.142/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.143/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.144/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.145/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.146/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.147/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.148/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.149/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.150/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.151/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.152/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.153/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.154/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.155/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.156/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.157/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.158/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.159/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.160/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.161/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.162/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.163/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.164/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.165/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.166/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.167/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.168/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.169/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.170/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.171/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.172/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.173/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.174/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.175/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.176/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.177/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.178/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.179/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.180/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.181/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.182/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.183/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.184/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.185/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.186/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.187/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.188/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.189/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.190/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.191/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.192/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.193/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.194/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.195/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.196/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.197/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.198/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.199/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.200/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.254/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet 192.168.249.71/24 brd 255.255.255.255 scope global secondary ens5
       valid_lft forever preferred_lft forever
    inet6 fe80::e2cb:4eff:fe48:4e28/64 scope link
       valid_lft forever preferred_lft forever
3: wls1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 00:25:d3:cd:e0:4f brd ff:ff:ff:ff:ff:ff
4: tun0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 100
    link/none
    inet 10.8.0.1/24 brd 10.8.0.255 scope global tun0
       valid_lft forever preferred_lft forever
    inet6 fe80::f3c8:a059:15d5:5ec7/64 scope link flags 800
       valid_lft forever preferred_lft forever

Полное содержимое /etc/network/interfaces. /etc/network/interfaces.d/пусто.

root@placeholder:~# cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto ens5
allow-hotplug ens5
iface ens5 inet dhcp

решение1

Я решил эту проблему.

В своем ответе я отметил, что получение IP-адресов работает нормально, а вот освобождение аренды — нет.

Я проверил /etc/dhcp/и нашел два интересных каталога:

root@placeholder:~# ls -lah /etc/dhcp/
total 744K
drwxr-xr-x   4 root root 4.0K Feb 17 08:00 .
drwxr-xr-x 104 root root 720K Feb 18 11:57 ..
-rw-r--r--   1 root root 1.4K Nov 26  2016 debug
drwxr-xr-x   2 root root 4.0K Aug 21  2010 dhclient-enter-hooks.d
drwxr-xr-x   2 root root 4.0K Feb 17 13:46 dhclient-exit-hooks.d
-rw-r--r--   1 root root 1.7K Dec 25 22:41 dhclient.conf

Я только что узнал, что dhclientна самом деле есть хуки для случаев 1.) получения аренды DHCP и 2.) освобождения аренды DHCP. .dКаталоги содержат скрипты bash, которые запускаются при срабатывании упомянутых событий.

Поскольку сервер испытывал трудности с освобождением DHCP-аренды, я проверил dhclient-exit-hooks.d. Конечно, там был неисправный скрипт. Там был sendmailскрипт, который всегда терпел неудачу, несмотря на возврат 0 (отсутствует каталог, так как sendmailбыл удален).

Связанный контент