freebsd-questions Digest, Vol 634, Issue 2

[Manish Jain]

On Tue, Jul 26, 2016 at 6:40 PM, Manish Jain <bourne.identity at hotmail.com> wrote:
Try mtr instead of ping (in ports) -- it shows you /where/ the packets are being lost. 'netstat -i' is also a good thing to check. If there are any packet errors, particularly if they are going up over time, then there's a physical problem somewhere on your local network. Frequently this is due to bad ethernet cables, but it could be some more expensive bit of hardware going wonky. Also, you need to do: service netif restart && service routing restart to completely refresh your network interfaces. Not restarting the routing explains at least part of what you're seeing. This sort of problem is almost never down to malfeasance -- the black hats would typically rather have control over your fully working hardware and will frequently try and avoid doing anything that would lead to being discovered. Most likely it's a software configuration problem, or failing that, hardware failure.


I just happened to have a network loss. 'mtr www.freebsd.org' comes up with an empty window (unlike previously when the mtr window listed many hosts on the route)

Running 'netstat -i' twice at an interval of about 1 minute produced the following :

/usr/home/bourne # date && echo && netstat -i
Tue 26 Jul 2016 19:08:12 IST

Name    Mtu Network       Address              Ipkts Ierrs Idrop    Opkts Oerrs  Coll
re0    1500 <Link#1>      50:46:5d:66:fd:10    13894     0     0    11581     0     0
re0       - 192.168.1.0   192.168.1.3          13639     -     -    11568     -     -
re0       - fe80::5246:5d fe80::5246:5dff:f        0     -     -        5     -     -
lo0   16384 <Link#2>                             698     0     0      698     0     0
lo0       - localhost     ::1                    348     -     -      348     -     -
lo0       - fe80::1%lo0   fe80::1%lo0              0     -     -        0     -     -
lo0       - your-net      localhost              350     -     -      350     -     -

/usr/home/bourne # date && echo && netstat -i
Tue 26 Jul 2016 19:09:22 IST

Name    Mtu Network       Address              Ipkts Ierrs Idrop    Opkts Oerrs  Coll
re0    1500 <Link#1>      50:46:5d:66:fd:10    13983     0     0    11655     0     0
re0       - 192.168.1.0   192.168.1.3          13726     -     -    11642     -     -
re0       - fe80::5246:5d fe80::5246:5dff:f        0     -     -        5     -     -
lo0   16384 <Link#2>                             866     0     0      866     0     0
lo0       - localhost     ::1                    432     -     -      432     -     -
lo0       - fe80::1%lo0   fe80::1%lo0              0     -     -        0     -     -
lo0       - your-net      localhost              434     -     -      434     -     -

Then I ran (as root):
service netif restart
service routing restart

At this point, I get my network back  : - )

What would this mean ? Is this a software problem, or some of my hardware has started failing ?

If you could kindly include my email address bourne.identity at hotmail.com in the cc list, I will be able to spot your reply more easily.

Thanks for your help
Manish Jain