Transcript Network Management

Network Management
Semester 3, Chapter 8
Allan Johnson
LAN Management
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This chapter deals mainly with the
management of LANs. Although the content
is not covered on the CCNA exam, it is
covered on the Comp TIA Net+ exam.
In addition, network management is when
the real work begins for a net admin.
Topics covered include:
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Documentation
Security
Network Performance
Server Administration
Troubleshooting
Network Documentation
Documentation
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Documenting the network, including:
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Cut sheet diagrams
MDF & IDF layouts
Server/workstation configurations
Software installed
Maintenance records
Security & user policies
...is the most critical component of good
network management.
Documentation is also the least implemented
component of network administration.
MDF & IDF Layouts
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The Physical and Logical layouts of all
wiring closets includes:
physical location of rack mounts,
equipment and servers
 patch panel labeling scheme for identifying
cable terminations
 Configuration details of all equipment
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Server/Workstation Configurations
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Includes details about:
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Hardware specifications
• Make & model
• Number & type of drives
• Cards installed
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Physical location & Logical addressing
• IP and MAC address
• Subnet
• Topology
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Purchase date and warranty information
Software & Maintenance Records
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Software listings include:
All software installed on each computer
 The standard configuration used for each
type of workstation
 Operating system information
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Maintenance records assist net admin
to anticipate potential problems and
include:
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All repairs and upgrades made to a
computer
Security & User Documents
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Physical Security
How are MDFs & IDFs locked
 Who has access to MDFs & IDFs
 How are host devices protected (security
cables, etc.)
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Soft Security
User policies & rights outlining what is and
what is not permissible on the network
 Password protection
 Firewall support
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Network Security
Security
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Network security includes two major
components:
Controlling Access
 Data Protection and Recovery
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Access
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The network policy established during the
documentation phase determines the criteria
used to select passwords, such as:
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password length
aging of passwords
time of day access is allowed
Acceptable Use Policies make sure users are
aware of the company’s definition of what is
allowed and not allowed on the network. It
also normally includes consequences for
violation of the policy.
Data Recovery
Data recovery, the second component
of security, involves protecting data
from loss
 Methods for protecting data include:
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Tape backup
 Fault tolerance
 Controlling Environmental Factors
 Power Conditioning
 Preventing Virus Corruption
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Tape Backup
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Magnetic tapes are the most popular media
used for backing up data because of the cost
and capacity.
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They are much cheaper than removable hard
drives
Tape backups record and restore data
sequentially.
This can make it difficult to find a particular
file. However, tape backups are used to fully
restore all lost data.
Most Tape Backup systems use an archive bit
set to on or off. If the bit is on, then the
data has been changed since the last backup.
Types of Tape Backup Systems
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Several options are available when using
tapes.
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Full backup--all files are backed up periodically
Incremental and Differential backups--uses an
archive bit to determine if a file has been created
or modified since the last full backup
Copy backup--backs up user selected data to tape
Daily backup--backs up data created or modified
for that day
Fault Tolerance
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Fault tolerance involves establishing redundancy
techniques to keep a system up and running
when a failure occurs.
RAID (Redundant Array of Inexpensive Disks)
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RAID 0--stripes data across multiple disk; no
redundancy
RAID 1--(mirroring) provides redundancy by writing all
data to two or more drives
RAID 2--no longer used because of expense
RAID 3/4--stores parity on one disk; 3 stripes at the
byte level and 4 stripes at the block level across
remaining disks.
RAID 5--similar to 3/4 but stripes data with parity
across multiple drives. Requires at least 3 drives. 5
drives is ideal.
Environmental Factors
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Electrical Static Discharge can approach
20,000 volts and fry sensitive computer
components
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Protect against by grounding yourself using
grounding strap before working on computers
Dust and dirt should be avoided. Periodically
clean keyboards, monitors, and towers
Avoid excessive heat
Follow TIA/EIA 568A standards to avoid EMI
and RFI noise
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For example, Shielded Twisted Pair (STP) cable is
a possible solution to prevent EMI/RFI corruption
of data.
Power Conditioning
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Power conditioning is the process of
implementing procedures to control the
power supplied to your network. They
include:
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Isolating Transformer--to control voltage spikes
and high frequency noise
Regulators--to maintain a constant level of voltage
Line Conditioner--an isolating
transformer/regulator combination.
Uninterruptible Power Supply--maintains a
charged battery to supply voltage to devices in
the event of a power failure.
Software Viruses
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Preventing software viruses is the final topic
under network security. Types include:
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Worm--a program that spreads across computers and
usually reproduces copies of itself in a computer’s
memory
Virus--a program that usually has a negative effect on
executable programs
Trojan Horse--destructive program disguised as a
game, utility or other application
Preventing viruses includes...
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Know where your data is coming from
Avoid allowing others to use floppies on your computer
Maintain updated virus checking software
Network Performance
Monitoring the Network
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Part of documenting the network is
establishing baselines for the various
performance issues including...
Bandwidth utilization
 Collision counts
 Broadcast traffic
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A baseline sets the acceptable
performance of the network, but must
be updated as the network is updated
or expanded.
Server Administration
Types of Networks
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Peer-to-Peer Networks
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Also known as a Workgroup Network, it is
designed for a small number of users.
No more than 10 devices should be on one peerto-peer network.
Advantages: relatively easy to configure, users
control resources, no dedicated server needed
Disadvantages: no central management
Client-Server Networks
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Uses a dedicated server running a NOS to control
resources and manage the network.
Types of Client-Server NOSs
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UNIX
Open standard with proprietary versions
offered by HP, IBM, and Sun (among
others) as well as a free versions (FreeBSD
and Linux).
 Multi-user, multi-tasking environment using
NFS security.
 Kernel based which isolates the hardware
layer from improperly operating
applications.
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Types of Client-Server NOSs
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NetWare
various versions as discussed in Ch. 7
 uses two file services: FAT and DET
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Windows NT/2000/2003
uses domains to control services with
Domain Controllers and Active Directory.
 Similar to UNIX except uses a different file
system structure
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Network Troubleshooting
Scientific Method
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Network troubleshooting is a systematic
process that uses the scientific method:
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Identify the network/user problem
Gather data about the network/user problem
Analyze data and come up with possible solutions
Choose and implement best solution
Evaluate solution’s success and modify data
collected, if necessary
If problem still exists, return to Step 3.
Typical Troubleshooting Scenario
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User calls and says he can’t access the
network (problem identified).
Gather data by asking the user questions,
checking logs, and hardware configurations.
Analyze the data collected to determine
possible solutions. Check the physical layer
by pinging the user. If unsuccessful, ping
the NIC from the the user’s computer using
the loopback address: 127.0.0.1. Continue
to ping along the network to find problem.
If no problem, then check software.
Typical Troubleshooting Scenario
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Implement the best solution to solve
the problem.
Evaluate the implemented solution to
see if the problem has been solved. If
not, return to Step 3.