GLOBAL:
#no logging consoloe: 
#no domain-lookup
#line console 0
line)#no execute-timeout
line)#length 35

STP: SPANNING TREE

• No. of  BPDU pakcet recived and send at an interface
• show spanning-tree int f0/0 detail | incl [BPDU|send|recived]
• clear interface STP counters
• clear spanning-tree counter
• 
  
• Making router send stp information
• Router(config)#brdige 1 protocol iee
•                       # int f0/0
•                           -if)# bridge-group 1
•                           -if)# end

switchport access vlan id

• When other vlan containg packets transfer from this access port will be dropped.
• Assigned on switch ports connected to routers & hosts(servers) only

caution

• If the VLAN that the port is assigned to does not exist in the database, the port is disabled until the VLAN is created.

ip MTU

• To set the maximum transmission unit (MTU) size of IP packets that are sent on an interface, use the ip mtu command in interface configuration mode.
•  To restore the default MTU size, use the no form of this command.
• 
  

ip mtu bytes

no ip mtu

• 
  
• The default MTU value depends on the interface medium. The following table lists the default MTU values 
• according to media types.
• Default Media MTU Values
• Ethernet: 1500
• Serial: 1500
• Token Ring: 4464
• ATM: 4470
• If an IP packet exceeds the MTU size that is set for the interface, Cisco software will fragment the IP packet.
• for more info se doc

Question:

Normalize the packet flows for the link by adjusting the MTU so that each IP packet takes no more than 10ms to be sent. ?
ANS: 

• find the MTU value,
• this mtu vlaue is equal to the ip packet size send in 10ms

bandwidth = 128kbps

128kbps = 128 kilo bits per second

              

second1000milliseconds(ms)

• from above simple calculations for every one millisecond 16bytes wille be send
• for 10 milliseconds is 10times of 16bytes i.e 160bytes
• then required mtu value is 160bytes

Fair-queue

• Effective with Cisco IOS XE Release 2.6, Cisco IOS Release 15.0(1)S, and Cisco IOS Release 15.1(3)T, the fair-queuecommand is hidden in interface configuration mode.
• To enable weighted fair queueing (WFQ), use the fair-queue command in interface configuration or policy-map class configuration mode.

fair-queue [congestive-discard-threshold [dynamic-queues [reservable-queues]]]

no fair-queue

      

• congestive-discard-threshold: 
• (Optional) Number of messages allowed in each queue.
• When a conversation reaches this threshold, new message packets are discarded.
• If you have hierarchical queueing framework (HQF) configured, then the values are 16 to 4096.
• dynamic-queues :
• (Optional) Number of dynamic queues used for best-effort   conversations (that is, a normal conversation not requiring any special network services).
• reservable-queues 
• (Optional) Number of reservable queues used for reserved conversations in the range 0 to 1000. The default is 0.
• Reservable queues are used for interfaces configured for features such as Resource Reservation Protocol (RSVP).
• 
  
• Fair queueing is supported for all LAN and line (WAN) protocols except X.25, including LAPB and SDLC
• Because tunnels are software interfaces that are themselves routed over physical interfaces, fair queueing is not supported for tunnels. 
• Fair queueing is on by default for interfaces with bandwidth less than or equal to 2 Mbps.
• IP Precedence, congestion in Frame Relay switching, and discard eligible (DE) flags affect the weights used for queueing.
• 
  

FOR MORE INFO CISCO CMD REFFERENCE

Bandwidth

#bandwidth {intended bandwidth in kbps}

#bandwidth inherit {kbps}     

                        : Specifies how a subinterface inherits the bandwidth of its main interface.

#bandwidth receive {kbsp}      

                       :Enables asymmetric transmit/receive operations so that the transmitted (inherit kbps) and received bandwidth are different

• If the receive keyword is not used, by default, the transmit and receive bandwidths will be assigned the same value.
• We cannot adjust the actual bandwidth of an interface using this command.
• This is only a routing parameter. It does not affect the physical interface.
• For some media, such as Ethernet, the bandwidth is fixed; 
• for other media, such as serial lines, you can change the actual bandwidth by adjusting the hardware. For both classes of media, 
• you can use the bandwidth command to communicate the current bandwidth to the higher-level protocols.
• The bandwidth inherit command controls how a subinterface inherits the bandwidth of its main interface.
• The no bandwidth inherit command enables all subinterfaces to inherit the default bandwidth of the main interface, regardless of the configured bandwidth. 
• If the bandwidth inherit command is used without configuring a bandwidth on a subinterface, all subinterfaces will inherit the current bandwidth of the main interface. 
• If you configure a new bandwidth on the main interface, all subinterfaces will use this new value.
• If you do not configure a bandwidth on the subinterface and you configure the bandwidth inherit kbps command on the main interface, the subinterfaces will inherit the specified bandwidth.
• In all cases, if an explicit bandwidth setting is configured on an interface, the interface will use that setting, regardless of whether the bandwidth inheritance setting is in effect.
• 
  

Bandwidth Receipt      ?  (need update)