Tech Tip: Satellite Internet Down? Not always true

If you are on Seabourn and see the dreaded screen in the thumbnail below - don't assume the problem has anything to do with the satellite link - despite what they would have you believe.

 

We just had (another) one of those on Sojourn, so I decided to investigate using the PC in my room and using my satellite and internet networking knowledge.

 

PCs have a built-in tool called Trace Route - which probes the network and asks each computer between you and the destination to respond. It is usually very illuminating. Trace Route said about the path between my PC and Google.

 

C:\>tracert google.com

 

Tracing route to google.com [173.194.32.128]

over a maximum of 30 hops:

 

1 91 ms 87 ms 49 ms 192.168.45.1

2 72 ms 85 ms 27 ms 10.26.0.1

3 89 ms 89 ms 80 ms 151.124.182.125

4 917 ms 846 ms 898 ms 151.124.224.217

5 807 ms 1280 ms 864 ms 151.124.224.221

6 898 ms 1191 ms 826 ms GigabitEthernet2-0.GW4.MIA4.ALTER.NET [152.179.26.81]

7 976 ms 1226 ms 956 ms 0.so-1-1-3.XL4.MIA4.ALTER.NET [152.63.82.154]

8 1014 ms 829 ms 1001 ms 0.ae8.GW2.MIA19.ALTER.NET [140.222.231.225]

9 855 ms 961 ms 826 ms google-gw.customer.alter.net [152.179.236.242]

10 920 ms 1159 ms 1067 ms 209.85.253.74

11 892 ms 858 ms 1051 ms 74.125.37.192

12 933 ms 831 ms 951 ms 74.125.37.173

13 971 ms 887 ms 1133 ms 216.239.42.222

14 1167 ms 1008 ms 1073 ms 216.239.48.238

15 855 ms 950 ms 916 ms 216.239.58.121

16 1005 ms 955 ms 973 ms 74.125.37.92

17 1138 ms 1349 ms 1098 ms 209.85.247.72

18 1216 ms 1221 ms 1069 ms 72.14.236.249

19 1229 ms 1037 ms 1278 ms 72.14.236.242

20 980 ms 1309 ms 1009 ms 173.194.32.128

 

Trace complete.

What the above says is that while the Sojourn was advising the system was down,

 

 

• The path from my PC started with 3 'hops' on board. You can tell that as the response time was less than the typical 700ms required to go over a satellite link, and back.
  
• Hop 4 and onwards involved little messages going from my PC, over the satellite link, and back ... each progressively further until hop 20 got to Google and back in around 1000 milliseconds (= 1 second)
  

So far so good.

 

 

So I tried something else, like BT (the old British Telecom) in the UK.

C:\>tracert bt.co.uk

 

 

Tracing route to bt.co.uk [193.113.9.162]

over a maximum of 30 hops:

 

1 112 ms 42 ms 5 ms 192.168.45.1

2 91 ms 22 ms 84 ms 10.26.0.1

3 23 ms 114 ms 97 ms 151.124.182.125

4 854 ms 984 ms 966 ms 151.124.224.225

5 1027 ms 993 ms 837 ms 151.124.224.229

6 952 ms 804 ms 856 ms GigabitEthernet2-0.GW4.MIA4.ALTER.NET [152.179.26.81]

7 857 ms 1114 ms 1068 ms 0.so-1-1-3.XL3.MIA4.ALTER.NET [152.63.82.142]

8 894 ms 932 ms 919 ms 0.ae3.BR1.MIA19.ALTER.NET [140.222.225.111]

9 1126 ms 943 ms 873 ms 204.255.168.14

10 862 ms 857 ms 965 ms ae-3.r20.miamfl02.us.bb.gin.ntt.net [129.250.2.110]

11 961 ms 792 ms 969 ms ae-4.r23.asbnva02.us.bb.gin.ntt.net [129.250.2.86]

12 1090 ms 1038 ms 1125 ms ae-2.r25.amstnl02.nl.bb.gin.ntt.net [129.250.6.163]

13 869 ms 956 ms 1010 ms ae-1.r03.amstnl02.nl.bb.gin.ntt.net [129.250.2.147]

14 1067 ms 932 ms 929 ms ae-3.r03.londen05.uk.bb.gin.ntt.net [129.250.6.26]

15 945 ms 960 ms 1054 ms ae-5.r02.londen05.uk.bb.gin.ntt.net [129.250.6.229]

16 978 ms 915 ms 907 ms 82.112.115.186

17 924 ms 1149 ms 1011 ms 213.137.183.101

18 936 ms 1002 ms * 62.6.201.144

19 * 999 ms 1149 ms 193.113.9.162

While the Sojourn was advising the system was down,

 

• In 19 hops, we managed to get from my PC on the Sojourn to the UK, and back.
  

 

• The path included:
  
  • Miami, FL
    
  • Ashburn, VA
    
  • Amsterdam, Netherlands
    
  • London, England
    

   

At this point, it is very safe to conclude the Satellite link from the ship is definitely NOT down.

 

So when you see the dreaded SATELLITE INTERNET SYSTEM DOWN message as below, run your own Trace Route (using the tracert command at the CMD prompt) and see if it really is or not.

 

If the system does not come back after a while (presumably until some human somewhere re-boots a computer or other device) ... contact the ship's staff and show them your Trace Route and politely explain that the satellite link is not down - something else is.

 

;)

Edited April 14, 2016 by Ubiquiti

Your ping got through - did any http traffic? Mail? Try to ssh into a system? I'm sure you know this but, different traffic uses different ports or port ranges - so while your UDP tracert request went out on IIRC 33434, your http would have gone out on 80, ssh 23, mail 25/465/587.

 

Since the staff on board (at least IME) aren't actual techs more help desk types with a limited script, I'm curious what they could do other than perhaps make a phone call?

Q: did any http traffic? Mail? Try to ssh into a system?

A: Nothing else apart from the ICMP(tracert/ping) packets got through (HTTP, SSH, and other traffic on non-standard ports I use to access my 'home' system) - hence my deeper investigations. That tells me it was a networking problem; not a connectivity problem. And by Networking - I include and strongly suspect it was the managed WiFi firewall system used to manage guest passwords/access.

 

Q:I'm curious what they could do other than perhaps make a phone call?

A:With past networking issues , I have found there has always been at least one staff assigned to IT issues on board. If that person's skills are limited to rebooting the on board system, and calling the land-based experts, that is all that is needed.