Hi everyone,

I’me having trouble with a CentOS 7 guest running on a Hyper-V host. For some reason, the CentOS guest randomly drops its IP address. Running
“systemctl restart NetworkManager” on the console will restore IP
connectivity without a reboot. I think that DHCP is timing out, but I’m not sure what to do about it. Is there a way to tell NetworkManager to keep trying after a timeout?

Here are the versions of the kernel and NetworkManager:
Kernel: 3.10.0-693.11.1.el7.x86_64
NetworkManager: 1.8.0-11.el7_4.x86_64

Here are some pertinent logs:
Dec 23 03:30:26 myhost kernel: hv_utils: Using TimeSync version 3.0
Dec 23 03:30:27 myhost systemd: Time has been changed Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.3750]
device (eth0): link connected Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.3762]
device (eth0): DHCPv4 lease renewal requested Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.3889] dhcp4
(eth0): canceled DHCP transaction, DHCP client pid 7936
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.3890] dhcp4
(eth0): state changed bound -> done Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.3899] dhcp4
(eth0): activation: beginning transaction (timeout in 45 seconds)
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.4487] dhcp4
(eth0): dhclient started with pid 33165
Dec 23 03:30:33 myhost dhclient[33165]: DHCPREQUEST on eth0 to
255.255.255.255 port 67 (xid=0x5cb111f1)
Dec 23 03:30:33 myhost dhclient[33165]: DHCPACK from xxx.xxx.36.1
(xid=0x5cb111f1)
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5824] dhcp4
(eth0): address xxx.xxx.37.53
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5825] dhcp4
(eth0): plen 23 (255.255.254.0)
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5826] dhcp4
(eth0): gateway xxx.xxx.36.1
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5826] dhcp4
(eth0): lease time 7200
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5826] dhcp4
(eth0): nameserver ‘xxx.xxx.0.20’
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5826] dhcp4
(eth0): nameserver ‘xxx.xxx.0.30’
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5826] dhcp4
(eth0): domain name ‘example.com’
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5826] dhcp
(eth0): domain search ‘example.com.’
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5827] dhcp
(eth0): domain search ‘foo.example.com.’
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5827] dhcp
(eth0): domain search ‘dyn.example.com.’
Dec 23 03:30:33 myhost NetworkManager[788]: [1514017833.5827] dhcp4
(eth0): state changed unknown -> bound Dec 23 03:30:33 myhost dhclient[33165]: bound to xxx.xxx.37.53 — renewal in 3368 seconds. Dec 23 03:30:33 myhost dbus-daemon: dbus[726]: [system] Activating via systemd: service name=’org.freedesktop.nm_dispatcher’
unit=’dbus-org.freedesktop.nm-dispatcher.service’
Dec 23 03:30:33 myhost dbus[726]: [system] Activating via systemd: service name=’org.freedesktop.nm_dispatcher’
unit=’dbus-org.freedesktop.nm-dispatcher.service’
Dec 23 03:30:33 myhost systemd: Starting Network Manager Script Dispatcher Service… Dec 23 03:30:33 myhost dbus[726]: [system] Successfully activated service
‘org.freedesktop.nm_dispatcher’
Dec 23 03:30:33 myhost dbus-daemon: dbus[726]: [system] Successfully activated service ‘org.freedesktop.nm_dispatcher’
Dec 23 03:30:33 myhost systemd: Started Network Manager Script Dispatcher Service. Dec 23 03:30:33 myhost nm-dispatcher: req:1 ‘dhcp4-change’ [eth0]: new request (4 scripts)
Dec 23 03:30:33 myhost nm-dispatcher: req:1 ‘dhcp4-change’ [eth0]: start running ordered scripts… Dec 23 03:40:42 myhost kernel: hv_utils: Using TimeSync version 3.0
Dec 23 03:40:43 myhost systemd: Time has been changed Dec 23 03:40:49 myhost NetworkManager[788]: [1514018449.4566]
device (eth0): link connected Dec 23 03:40:49 myhost NetworkManager[788]: [1514018449.4583]
device (eth0): DHCPv4 lease renewal requested Dec 23 03:40:49 myhost NetworkManager[788]: [1514018449.4693] dhcp4
(eth0): canceled DHCP transaction, DHCP client pid 33165
Dec 23 03:40:49 myhost NetworkManager[788]: [1514018449.4694] dhcp4
(eth0): state changed bound -> done Dec 23 03:40:49 myhost NetworkManager[788]: [1514018449.4703] dhcp4
(eth0): activation: beginning transaction (timeout in 45 seconds)
Dec 23 03:40:49 myhost NetworkManager[788]: [1514018449.4781] dhcp4
(eth0): dhclient started with pid 33440
Dec 23 03:40:49 myhost dhclient[33440]: DHCPREQUEST on eth0 to
255.255.255.255 port 67 (xid=0x2f112c1)
Dec 23 03:40:52 myhost dhclient[33440]: DHCPREQUEST on eth0 to
255.255.255.255 port 67 (xid=0x2f112c1)
Dec 23 03:40:57 myhost dhclient[33440]: DHCPREQUEST on eth0 to
255.255.255.255 port 67 (xid=0x2f112c1)
Dec 23 03:41:02 myhost dhclient[33440]: DHCPDISCOVER on eth0 to
255.255.255.255 port 67 interval 6 (xid=0xe5feb70)
Dec 23 03:41:08 myhost dhclient[33440]: DHCPDISCOVER on eth0 to
255.255.255.255 port 67 interval 10 (xid=0xe5feb70)
Dec 23 03:41:18 myhost dhclient[33440]: DHCPDISCOVER on eth0 to
255.255.255.255 port 67 interval 12 (xid=0xe5feb70)
Dec 23 03:41:30 myhost dhclient[33440]: DHCPDISCOVER on eth0 to
255.255.255.255 port 67 interval 16 (xid=0xe5feb70)
Dec 23 03:41:34 myhost NetworkManager[788]: [1514018494.9605] dhcp4
(eth0): request timed out Dec 23 03:41:34 myhost NetworkManager[788]: [1514018494.9612] dhcp4
(eth0): state changed unknown -> timeout Dec 23 03:41:34 myhost NetworkManager[788]: [1514018494.9713] dhcp4
(eth0): canceled DHCP transaction, DHCP client pid 33440
Dec 23 03:41:34 myhost NetworkManager[788]: [1514018494.9714] dhcp4
(eth0): state changed timeout -> done

Thanks, Jason

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