nms

Network Troubleshooting/NMS

Client Networking MAC

IP Settings• IP

• Netmask/Subnet Mask

• Gateway

• DNS

Tools• ipconfig

• Winipcfg

• nslookup

• telnet

• ping

• tracert

Client Networking - MAC

MAC Address

• Media Access Control

• 48 bits

• Represented as 12 hexadecimal characters or 6

delimited octets (in hex)

Client Networking – IP Settings

IP Address

• 32 bits

• Represented as 4 octets separated by

periods

Subnet Mask

• Bit mask to determine network, broadcast

and local addresses

Client Networking – IP Settings

Gateway – Default Route

• If the address is not within the local network it is

sent to the default route address

• UI network standards use the first usable

network IP address as the gateway

DNS – Domain Name System

• Resolves human readable name to IP address

Client Networking - Tools

ipconfig


ipconfig /all | more


winipcfg


winipcfg – More Info


Nslookup

• Windows NT/2000/XP

• Displays DNS information

– Includes CNAME/Aliases

– Can be used for alternate DNS attribute lookup

• No arguments enters interactive mode


Nslookup


telnet

• Useful for connecting to tcp service ports

• telnet <hostname> <port or service name>

• Uses local services file to resolve port

• Some common service names and ports

– smtp = 25

– pop = 110

– imap = 143

telnet smtp.uidaho.edu smtp


ping

• Packet INternet Groper

• Sends ICMP echo requests to remote host

• Not always reliable, use telnet if possible

• ping <hostname or ip address>

• ping –t <host> (continuous ping)


ping


ping

• Using ping for troubleshooting

– ping 127.0.0.1

Tests local tcp/ip stack

– ping <local ip>

Tests hardware/network device driver

– ping <gateway>

Tests local subnet communication

– ping <remote ip>

Tests complete trip to destination

• Warning: using a host name relies on name resolution


tracert (traceroute)

• Uses ICMP

• Displays hops/routes in path to host

NMS

Navigation• Physical Layer

• Network Layer

• Looking Up Information– Wallplate

– Network

– MAC

• Entering Information

Troubleshooting• MAC Record on Proper Network

• View Port Counters

NMS - Navigation

Physical Layer (physical assets)

• Buildings, closets, hubs, hub ports, wallplates

Network Layer (logical assets)

• Networks, MAC records, Domains

NMS - Navigation

Wallplate

• Format: <building><closet><room><wallplate><port>

• Example:

– 001a132-01b

– Building = 001

– Closet = A

– Room = 132 (pad to 4 characters with hyphen)

– Wallplate = 01

– Port = B (most ports are A = top, B = middle, C = bottom)

UI standards are to populate A with phone, B with data and leave

C available. Phones or data can be used in ANY port

NMS - Navigation Wallplate

• Searching for a wallplate will return its hub/switch port or phone association.

• “No reference to wiring code” means there is either no association/patch or the wallplate does not exist. Leave off the port to see if the wallplate is valid (ex. 001a132-01)

• A hub/switch port is the location on the hub/switch device where the wallplate terminates.

• Hub Port Format: <building><closet><stack><stack unit><port>– Example: 001a1106

– Building = 001

– Closet = A

– Stack = 1

– Stack Unit = 1 (switches cannot be stacked so they are always 1)

– Port = 06

NMS - Navigation

VLAN

• Virtual LAN

– The ability to connect multiple devices together as though they

were on the same physical network, regardless of the true

underlying network

• All NMS “networks” are part of defined VLANs

• NMS currently lacks the ability to lookup VLANs and the

networks contained within a VLAN

• The gateway for a network will show the VLAN the

network is a member of

NMS - Navigation

Network• 129.101 is a B class IP network

• UI subnets 129.101 into 4 subnet classes– A = 1024 addresses (255.255.240.0)

– B = 256 addresses (255.255.255.0)

– C = 64 addresses (255.255.255.192)

– D = 16 addresses (255.255.255.240)

• Currently each MAC record resides in a single network

• Each hub/switch port is on a single “network”

• Networks can have multiple alternate/secondary networks – part of the same “VLAN”

NMS - Navigation

Network

• Determine the network by clicking “Up to Hub”

when viewing a hub/switch port. The default

network for the device is displayed.

– Warning: switches can be in multiple networks. The

default network is not necessarily the same as the

port. View port counters will display the vlan for the

switch port.

NMS - Navigation

MAC

• MAC records can be found through mac address, ip or

dns name.

• Records are associated with a single network.

• Network history is determined by an active process

running every few minutes scanning network devices.

– Warning: network history may not be correct due to a number of

issues (if the remote system was on at the time of polling, if the

hub/switch is capable of being polled). Use “View Port

Counters” to view real-time usage.

NMS - Navigation

MAC

• Creating MAC Records

– Determine proper network based on wallplate

– Select “Create a new MAC record” on main network

layer menu or select “Create a MAC record on this

network” after select “Up to Hub”.

– MAC record information is propagated to all services

in ~10 minutes.

NMS - Navigation

Troubleshooting

• MAC record is not on the proper network

– View wallplate and hub default network to determine

proper network (or secondary network)

• View Port Counters

– Link signal can be used to determine proper wallpate

to port association

– Current known MAC address

– Number of errors

NMS - Navigation

Troubleshooting

• NRG Graphs under “Port number”

– When viewing a port/wallplate id, the “Port number” is

linked to NRG graph data for network activity on the

port

nms

Documents