[Tech] Need help with the Internet at the Mentone ("slow" ... latency? and/or connectivity?)

Michael Paoli Michael.Paoli at cal.berkeley.edu
Tue Jun 28 19:06:41 PDT 2016


You might want to start with closest hop router.
It's likely default.  Can find that with the ip command.
If that command isn't on (your mere mortal user) PATH,
it's typically in /sbin or /usr/sbin, so could use absolute
(starts with /) path to the program instead (e.g. prepend ip
with /sbin/ or /usr/sbin/).  So e.g. I find from my example
host:
$ ip r s
default via 198.144.194.233 dev br0
192.168.55.0/24 dev br0  proto kernel  scope link  src 192.168.55.1
192.168.122.0/24 dev virbr0  proto kernel  scope link  src 192.168.122.1
198.144.194.232/29 dev br0  proto kernel  scope link  src 198.144.194.235
$
So, most notable there, would be the IP that shows in the
default route:
198.144.194.233
Interestingly/oddly that command didn't show my IPv6 bits, but that
may not matter for your setup.  Anyway, giving option to just show
the IPv6, I have:
$ ip -6 r s
2001:470:66:76f::1 dev he-ipv6  metric 1024
2001:470:66:76f::/64 dev he-ipv6  proto kernel  metric 256
fe80::/64 dev br0  proto kernel  metric 256
fe80::/64 dev he-ipv6  proto kernel  metric 256
fe80::/64 dev vnet0  proto kernel  metric 256
default via 2001:470:66:76f::1 dev he-ipv6  metric 1024
$
... so in that case, for the IPv6 portion, default router IP:
2001:470:66:76f::1

Anyway, should be able to ping your default router IP(s),
ping(1) for IPv4, ping6 for IPv6, e.g.:
$ ping -n -c 5 198.144.194.233
PING 198.144.194.233 (198.144.194.233) 56(84) bytes of data.
64 bytes from 198.144.194.233: icmp_seq=1 ttl=255 time=29.3 ms
64 bytes from 198.144.194.233: icmp_seq=2 ttl=255 time=10.6 ms
64 bytes from 198.144.194.233: icmp_seq=3 ttl=255 time=11.2 ms
64 bytes from 198.144.194.233: icmp_seq=4 ttl=255 time=11.3 ms
64 bytes from 198.144.194.233: icmp_seq=5 ttl=255 time=12.1 ms

--- 198.144.194.233 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4003ms
rtt min/avg/max/mdev = 10.676/14.960/29.305/7.188 ms
$
and for IPv6:
$ ping6 -n -c 5 2001:470:66:76f::1
PING 2001:470:66:76f::1(2001:470:66:76f::1) 56 data bytes
64 bytes from 2001:470:66:76f::1: icmp_seq=1 ttl=64 time=15.0 ms
64 bytes from 2001:470:66:76f::1: icmp_seq=2 ttl=64 time=15.4 ms
64 bytes from 2001:470:66:76f::1: icmp_seq=3 ttl=64 time=15.0 ms
64 bytes from 2001:470:66:76f::1: icmp_seq=4 ttl=64 time=15.1 ms
64 bytes from 2001:470:66:76f::1: icmp_seq=5 ttl=64 time=14.2 ms

--- 2001:470:66:76f::1 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4005ms
rtt min/avg/max/mdev = 14.216/14.971/15.440/0.426 ms
$

You may also be able to isolate issues with traceroute, e.g. using
TCP with traceroute (need to be superuser ("root") to do this, so
sudo or as root, so, e.g.:
$ dig -t A www.google.com. +short
172.217.1.228
$ sudo traceroute -n -T -p 443 172.217.1.228
traceroute to 172.217.1.228 (172.217.1.228), 30 hops max, 60 byte packets
  1  198.144.194.233  10.857 ms  12.343 ms  14.765 ms
  2  216.131.94.209  16.936 ms  19.052 ms *
  3  * * 173.205.60.193  21.125 ms
  4  89.149.180.42  30.564 ms * 141.136.106.206  33.101 ms
  5  199.229.230.134  37.055 ms  37.975 ms  41.609 ms
  6  216.239.49.168  42.531 ms  34.588 ms  39.405 ms
  7  64.233.174.91  46.842 ms  49.246 ms 209.85.246.38  53.627 ms
  8  64.233.174.204  65.770 ms  58.009 ms  57.582 ms
  9  209.85.248.124  55.769 ms 64.233.174.191  56.836 ms  55.163 ms
10  * * *
11  172.217.1.228  43.975 ms  42.202 ms  37.240 ms
$


> From: "Christian Einfeldt" <einfeldt at gmail.com>
> Subject: Re: [Tech] Need help with the Internet at the Mentone  
> ("slow" ... latency? and/or connectivity?)
> Date: Tue, 28 Jun 2016 11:01:07 -0700

> Hi Mike,
>
> How do I get the IP address for the switch?  Googling doesn't seem to be
> helping me here, I just be asking the wrong question?
>
> The speedtest does work on that machine from home using the same machine
> and the same ethernet cable.  Thanks!
>
> On Tue, Jun 28, 2016 at 8:05 AM, Michael Rojas <
> ledworldwide.solutions at gmail.com> wrote:
>
>> Hi Christian,
>>
>> It looks like you are experiencing heavy packet loss from the lobby.  My
>> next step would be to ping a switch or server on the local network from the
>> lobby to try and narrow down where the problem lies (bad switch/router
>> config, bad cable ...?)
>>
>> Why the speed test didn't work from the basement is a mystery though.  Is
>> the speedtest working from another location (from home)?
>>
>> -Mike Rojas-
>>
>>
>>
>> On Fri, Jun 24, 2016 at 11:46 PM, Christian Einfeldt <einfeldt at gmail.com>
>> wrote:
>>
>>> Hi, Thanks for your thoughts, Michael.
>>>
>>> On Fri, Jun 24, 2016 at 1:44 PM, Michael Paoli <
>>> Michael.Paoli at cal.berkeley.edu> wrote:
>>>
>>>> Sounds like you've got latency issue, not necessarily bandwidth
>>>> issue(s).  The very long times on ping to Google would
>>>> reflect latency issues.  It's not uncommon for ISPs to support
>>>> large buffering - this gives 'em a slight edge in most typical
>>>> bandwidth tests ... and the cost of latency - as/when the
>>>> bandwidth is quite saturated, buffers fill, and hence latency
>>>> can be quite to even exceedingly high.  This can then trigger various
>>>> errors, such as DNS timeouts - which might well be why your
>>>> "speed tests" failed - but can't really tell from the limited output
>>>> that check provided (the CLI tool may have options for more details,
>>>> and/or one may use additional diagnostics to check what's happening
>>>> when the speed test is attempted - which may then make clear why the
>>>> test is failing).  Shared usage of bandwidth can be an issue, e.g.
>>>> multiple computers, etc., and single "pipe" of some fixed limited
>>>> bandwidth to Internet.  If one machine is hogging it all, or even
>>>> multiple are together trying to use all the bandwidth, that will
>>>> make it "slow" for them, and anything else attempting to share that
>>>> bandwidth.
>>>>
>>>> Anyway, realized and understand that bandwidth (speed), and latency
>>>> (how long does the trip take) are not the same thing.  Either may
>>>> be perceived as "slow", depending upon the nature of the usage.
>>>>
>>>> If, as you mention, you're having problems even doing the updates,
>>>> it's likely either issues with latency causing issues with DNS,
>>>> and/or more general connectivity issues (which may also be caused
>>>> by latency issues).  "Slow" - as in low bandwidth, will not
>>>> in-and-of-itself break "speed"tests or getting updates on-line ...
>>>> were it only a bandwidth issue, things would just take longer ...
>>>> possibly *much* longer.
>>>>
>>>> From: "Christian Einfeldt" <einfeldt at gmail.com>
>>>>> Subject: [Tech] Need help with the Internet at the Mentone
>>>>> Date: Fri, 24 Jun 2016 11:50:55 -0700
>>>>>
>>>>
>>>> Hi,
>>>>>
>>>>> Here are my questions:
>>>>>
>>>>>    1. Why did my speed tests fail in this situation?
>>>>>    2. Are the ping speeds normal for this situation?
>>>>>    3. What diagnostic tests can I run to isolate the slowness on this
>>>>>    system?
>>>>>
>>>>> As most people on this list know, Partimus is volunteering for a low
>>>>> income
>>>>> housing shelter in here in SF.  I have put in some quality legacy
>>>>> Lubuntu
>>>>> machines in the lobby for the residents to use.  These machines all have
>>>>> Intel Core 2 duo chips with 2 GB of RAM and are running Lubuntu 14.04.
>>>>> I
>>>>> use a similar machine at home, and have no problems with it.  This
>>>>> email is
>>>>> being written on such a machine at one of the other two homeless
>>>>> shelters.
>>>>> The residents routinely use these machines to watch YouTube video and
>>>>> use
>>>>> LibreOffice, etc., all without issue.  The machines are proven good.
>>>>>
>>>>> This is the third shelter to which we have given machines.  They don't
>>>>> have
>>>>> a budget for either the equipment or the tech support for these
>>>>> machines.
>>>>>
>>>>> Two of the three shelters have good speed on the Internet that goes to
>>>>> the
>>>>> machines.  (The shelters provide the Internet service).
>>>>>
>>>>> However, the third shelter, called the Mentone, has slow Internet
>>>>> speeds in
>>>>> the lobby.  I am not able to even do anything as basic as run sudo
>>>>> apt-get
>>>>> update, as the machine chokes on downloading the updates.
>>>>>
>>>>> The wiring is put in place by a company I will call the Maintenance
>>>>> Group
>>>>> (MG).  I have called both the MG and the ISP.  Both of them claim that
>>>>> they
>>>>> have no problems.  The ISP says that they are providing the usual 2
>>>>> Mbit /
>>>>> second that we expect here in the US for a configuration like this.
>>>>> The MG
>>>>> says that they have run a test on the wiring from the server to the
>>>>> lobby,
>>>>> and are not seeing any problems.
>>>>>
>>>>> The ISP is a good company that does not hate GNU-Linux.
>>>>>
>>>>> The ISP asked me to give them a speed test directly from the switch,
>>>>> which
>>>>> is located in the basement.  So I ran speed tests in the basement and in
>>>>> the lobby, and was unable to get the speed test to work.  Speed test has
>>>>> worked on this machine before.  Here are the two results:
>>>>>
>>>>> Lobby, where the Lubuntu machine is to be located:
>>>>>
>>>>> cje at cje-ultralap440:~$ speedtest-cli
>>>>>
>>>>> Retrieving speedtest.net configuration...
>>>>>
>>>>> Could not retrieve speedtest.net configuration: timed out
>>>>>
>>>>> cje at cje-ultralap440:~$ ifconfig
>>>>>
>>>>> eth0      Link encap:Ethernet  HWaddr 20:1a:06:04:64:42
>>>>>          inet addr:172.16.2.121
>>>>>
>>>>> basement, directly from the switch:
>>>>>
>>>>> cje at cje-ultralap440:~$ speedtest-cli
>>>>>
>>>>> Retrieving speedtest.net configuration...
>>>>>
>>>>> Could not retrieve speedtest.net configuration: timed out
>>>>>
>>>>> cje at cje-ultralap440:~$
>>>>>
>>>>> *My first question:  *I am not sure why this speed test failed.  Does
>>>>> anyone know?
>>>>>
>>>>> Since I couldn't run speedtest, I pinged google instead.  Here are the
>>>>> results from the lobby:
>>>>>
>>>>> cje at cje-ultralap440:~$ ping www.google.com
>>>>>
>>>>> PING www.google.com (216.58.192.4) 56(84) bytes of data.
>>>>>
>>>>> 64 bytes from nuq04s29-in-f4.1e100.net (216.58.192.4): icmp_seq=1
>>>>> ttl=52
>>>>> time=8.24 ms
>>>>>
>>>>> 64 bytes from nuq04s29-in-f4.1e100.net (216.58.192.4): icmp_seq=2
>>>>> ttl=52
>>>>> time=7.31 ms
>>>>> <snip>
>>>>>
>>>>> --- www.google.com ping statistics ---
>>>>>
>>>>> 16 packets transmitted, 12 received, 25% packet loss, time 15037ms
>>>>>
>>>>> rtt min/avg/max/mdev = 6.962/7.497/8.198/0.366 ms
>>>>>
>>>>> Here is the test from the basement:
>>>>>
>>>>> cje at cje-ultralap440:~$ ping www.google.com
>>>>>
>>>>> PING www.google.com (216.58.192.4) 56(84) bytes of data.
>>>>>
>>>>> 64 bytes from nuq04s29-in-f4.1e100.net (216.58.192.4): icmp_seq=1
>>>>> ttl=52
>>>>> time=8.24 ms
>>>>>
>>>>> 64 bytes from nuq04s29-in-f4.1e100.net (216.58.192.4): icmp_seq=2
>>>>> ttl=52
>>>>> time=7.31 ms
>>>>> <snip>
>>>>>
>>>>> --- www.google.com ping statistics ---
>>>>>
>>>>> 11 packets transmitted, 11 received, 0% packet loss, time 10015ms
>>>>>
>>>>> rtt min/avg/max/mdev = 7.022/7.816/8.519/0.451 ms
>>>>>
>>>>> cje at cje-ultralap440:~$
>>>>>
>>>>> *My second question*: Are these ping speeds normal?
>>>>>
>>>>> My third question: What can I do to find the problem with the system?
>>>>>
>>>>> Thanks!
>>>>>
>>>>> --
>>>>> Christian Einfeldt
>>>>>
>>>>
>>>>
>>>
>>>
>>> --
>>> Christian Einfeldt
>>>
>>> _______________________________________________
>>> Tech mailing list
>>> Tech at lists.partimus.org
>>> http://lists.partimus.org/listinfo.cgi/tech-partimus.org
>>>
>>>
>>
>
>
> --
> Christian Einfeldt
>




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