Re: networkmanager spawned dhcpcd and kill it consistantly?

[cheng renquan <crquan gmail com>]

On Tue, Jun 12, 2012 at 12:33 PM, Dan Williams <dcbw redhat com> wrote:
> Is IPv6 perhaps enabled on that network, and perhaps an IPv6 router is
> sending router advertisements?  You could try to set the IPv6 method for
> this connection to  "ignored" in the connection editor, and see if that
> makes a difference.

Yes, IPv6 may be a major feature of this ATT Internet,

actually sometimes the above dhcpcd SIGTERM loop may not happen or may finish
after tens of SIGTERM rounds, and finally both IPv4 and IPv6 becoming
stably working:


# ps fuww -s 7855
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      7855  0.0  0.1 239120  7668 ?        Ssl  10:54   0:18
/usr/sbin/NetworkManager
root       762  0.0  0.0   8512   888 ?        S    20:16   0:00  \_
/sbin/dhcpcd -B -K -L -G -c
/usr/lib/networkmanager/nm-dhcp-client.action wlan0

# ip addr show wlan0
2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
    link/ether 00:24:d7:26:dd:20 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.121/24 brd 192.168.1.255 scope global wlan0
    inet6 2602:304:cf7b:e70:224:d7ff:fe26:dd20/64 scope global dynamic
       valid_lft 86400sec preferred_lft 14400sec
    inet6 fe80::224:d7ff:fe26:dd20/64 scope link
       valid_lft forever preferred_lft forever

# nslookup -query=aaaa ipv6.google.com 2001:4860:4860::8888
Server:		2001:4860:4860::8888
Address:	2001:4860:4860::8888#53

Non-authoritative answer:
ipv6.google.com	canonical name = ipv6.l.google.com.
ipv6.l.google.com	has AAAA address 2001:4860:4001:801::1013

Authoritative answers can be found from:

# ping6 2607:f8b0:4000:801::1013 -c4
PING 2607:f8b0:4000:801::1013(2607:f8b0:4000:801::1013) 56 data bytes
64 bytes from 2607:f8b0:4000:801::1013: icmp_seq=1 ttl=51 time=397 ms
64 bytes from 2607:f8b0:4000:801::1013: icmp_seq=2 ttl=51 time=90.4 ms
64 bytes from 2607:f8b0:4000:801::1013: icmp_seq=3 ttl=51 time=389 ms
64 bytes from 2607:f8b0:4000:801::1013: icmp_seq=4 ttl=51 time=173 ms

--- 2607:f8b0:4000:801::1013 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3002ms
rtt min/avg/max/mdev = 90.460/262.502/397.195/133.956 ms


In the above SIGTERM loop, I'm just curious who is sending such
SIGTERM signal to dhcpcd ?
is that NetworkManager ? and how to identify where is SIGTERM signal
coming from?

Thanks;