Solved

Internet connection issue

Posted on 2006-11-19
5
181 Views
Last Modified: 2013-11-29
I have a computer that is used to connect to internet with no problem, but after ISA server was installed it can not connect to internet anymore.

the question is if I was not told that ISA server was installed, how would I find out the reason why the computer can not connect to internet , which tools should I use or should I have used to find out?

thanks
0
Comment
Question by:jskfan
5 Comments
 
LVL 1

Expert Comment

by:dacz
ID: 17975078
get the IP address of your ISA server and make it your proxy server address to have an internet connection.
0
 
LVL 1

Assisted Solution

by:dacz
dacz earned 35 total points
ID: 17975096
0
 
LVL 6

Assisted Solution

by:_iskywalker_
_iskywalker_ earned 35 total points
ID: 17975181
first it is nice to know if you have an ip, then if you can ping your host or gateway, then you should contact the admin of the gateway to let you go through the internet. if you can you can ping www.experts-exchange.com and see if  it works, then you can traceroute this address and see which wroute it takes.
0
 

Author Comment

by:jskfan
ID: 17975200
my question was:
 How do I know that it was ISA server  blocking access to internet if I was not told by someone else that ISA server was installed in the computer?



0
 
LVL 79

Accepted Solution

by:
lrmoore earned 180 total points
ID: 17975330
That depends. Do you mean as a single end-user only - how can you determine that something was blocking your Internet access?
or as a systems administrator, what tools can you use to determine why you can't get Internet access, and could have determined that ISA had been installed somewhere?
or as a systems administrator, what tools can you use to know when something gets installed on one of your servers without you knowing about it?

All of these are really tough questions without simple answers.
Basically, if your Internet access goes down, then start by using the good old 7-layer OSI model, ground up.
Start with Layer1 - check/test all cables, outlets, plugs, etc
Layer2 = protocol checks, vlans, packet errors (duplex mismatch) etc
Layer3 = IP subnets/routes - ping/traceroute/route print/ ipconfig
Layer4 = name resolution/DNS/ firewall rules / proxy rules - Sniffer/Ethereal
Layer5-7 = permissions, credentials and applications. What's wrong with credentials/login? What's new application wise? What changed in any applications? What's different in this system that works and that one that doesn't? Group Policy is new, etc.  Sniffer/Ethereal can help determine these type issues
Layer 8 - 9 = politics, money and religion. Who make the new rules without communicating them to the masses? What governs most changes? Money, politics and religion. (Religion in the way some are religous Microsoft fanatics, some are religously anti-Microsoft fanatics, Cisco fanantics, anti-Cisco fanatics, etc)

None of those tools may ever tell you that it was specifically an unexpected ISA server showing up that was causing the problem. You might determine the IP address/mac-address of whatever it is blocking traffic, then you'd have to manually look at that system to see what was happening.

Do you have a change management process? If you did, then it would never allow that something as potentially disruptive to production as installing ISA could happen without everyone knowing about it. There are other automated tools available to determine and report system changes.
0

Featured Post

Easy, flexible multimedia distribution & control

Coming soon!  Ideal for large-scale A/V applications, ATEN's VM3200 Modular Matrix Switch is an all-in-one solution that simplifies video wall integration. Easily customize display layouts to see what you want, how you want it in 4k.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
OSPF - Convergence & Downtime 9 37
Internet link load balancer 6 67
exclude a user from a deny permisssion 4 57
software inventory tools 3 40
If your business is like most, chances are you still need to maintain a fax infrastructure for your staff. It’s hard to believe that a communication technology that was thriving in the mid-80s could still be an essential part of your team’s modern I…
ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…

829 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question