4-2 Network Support

Some sections of the network+ blueprint concern installation/troubleshooting scenarios and, this is where I would like to ask for input from you.

If you create your own scenario(s) please consider posting them here to help others. Use the contact link on the top of this page to E-mail me, and I will post them giving full credit to you.

Thanks.

You are setting up a small office LAN. The office already has 12 windows 98 machines running off a netware 3.11 server. They need to add more clients to the network add upgrade to a new faster server. Their bugget will not allow for additional netware client licences, and they want you to keep both costs and complexity at a minimum. They ask you to set them up with a linux server. Once the the server is installed and running, how do you setup the network to allow the client computers to connect to the Linux server(choose all that apply) Assume the windows clients were only setup to network with the netware server

• a.Setup NFS on the linux server
• b.install services for Unix (sfu) on the windows machines
• c.install tcp/ip on the windows machines
• d.install WINE on the Linux server e.setup samba on the Linux server

Answer: c,e

Explanation: The best way to connect windows clients to linux (or other nixes) is samba. samba allows linux to use smb/cifs on which windows file sharing is built. ( This is not the offical position of microsoft, but on that later) With samba installed and properly configured on the server, the windows clients will be able to connect to the server tcp/ip properly configured.

Whereas NFS would do the job, it would require third party software to work with the windows 98 clients and would not likely be transparent to the end users. SFU is only included in windows 2000, not windows 98. Note that ( big surprise here) microsoft highly recommends the NFS and SFU be used for windows 2000 networks. WINE is a windows emulator and would not help for network connectivity.

The following scenario was send in by Ted

You are hired to replace a contractor on a large job. The contractor wired a large building with cat 5 cabling, but failed to connect all of the drops to the bank of switches. They also did not label anything. You are now asked to setup a room with 4 jacks(RJ45) but only 3 of these jack are hot. You realize that you need to find the other end of this cable on the patch pannel and connect it to the proper switch. What tool is the best to use to find the other end of the cable?

• a.optical tester
• b.protocol analyzer
• c.multimeter
• d.Tone generator

Answer: d The tone generator could be connected at the jack and the probe used to find the other end

Explanation: An optical test would help to test fiberoptics but not cat 5 cable While a multimeter could, in theory be used, in most cases it is impractical at best and usually impossible. A protocol analyzer would be useless in this case. There is no traffic to analyze .

Thanks to Kristen for this example.

Example: Your network uses a star topology with 48 users and 3 hubs, one per department. Each hub handles 16 users. Three users in one of the departments cannot access the network server. What should you check first?

• a) Network connections on the three users' computers
• b) Review logon procedures with the users
• c) The routing table in the router
• d) The departmental hub

Solution: The departmental hub

Explanation: A star configuration consists of a network hub with several ports. Network cables spread out from it and connect to each computer. A basic star has only one computer on each network cable extending from the hub. When one hub goes down, each user connected to that hub loses network access. When several users connected through the same hub report problems, check the hub before checking individual computers.

The routing table or logon procedures are unlikely to affect only three users. Network connections on three users' computers would be unlikely to fail at the same time.

The following scenario was send in by Ted

You are the network administrator for a small company with two subnets in two locations: Main office and branch office. Julie is the manager of the branch office. She reports that a new machine which was just installed will not connect with resources in the main office, but it can coonect with local machines. The networks are routed and use standard class C private addresses. Main office is 192.168.1.0/24 branch is 192.168.2.0/24 The output of ipconfig look like this

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix .: Smallco.local

IP Address. . . . . . .: 192.168.2.16

Subnet Mask . . . . . .: 255.255.128.0

Default gateway . . . . .: 192.168.2.1

What is the problem?

• a.ip address
• b.no DNS server is assigned
• c.subnet mask is wrong
• d.wrong default gateway

Answer: c Class C always has a mask of 255.255.255.0. As a result the new machine thinks that the 192.168.1.0 network is on its subnet.

Explanation: There is no evidence to sugest that the problem is the ip address. If there were a conflict you would gwt a 0.0.0.0 ip address

The symptoms could indicate a bad default gateway, but in this case, the default gateway address is on the correct subnet. Usually the router is assigned the fist usable address on the subnet, and that is what we had.

DNS server information is not displayed by ipconfig by itself. You would need to use ipconfig /all to see that