sat12 trobule shootting

7/27/2019 SAT12 Trobule Shootting

1/21


2/21

Failure descriptionCheck port by SHOW port command, and physicalport always keeps DOWN.

Check port by show port command, and physicalport always keeps UP, but losing package seriously

while pinging opposite end

WEI


3/21

I haven't received

yet!Data package loses

seriously while pinging

opposite end

WEI


4/21

Question 2:Finding that the physical port isD O W N w h ile checking router serial portstate,and notice the following signal states are:

DCD=UP DTR=DOWN DSR=UP RTS=DOWNCTS=UP Why?.

Answer:We know that DTR RTS signals are bothsent from DTE(data terminal),so maybe the DTEequipments did not connect well,Checking

whether the DTE equipments connect correctlyand whether cable or line has questions.

AWEI


5/21

Question 4:What's the difference betweenconfiguration port and backup port cable ofQUIDWAY router.

Solutions:Configuration port cable DB9(25) end isDCE head, while backup port cable DB9(25) endis DTE head, In fact it also can be understoodeasily: the router is regarded as DCE while

configuring router, while which is regarded asDTE when the router connects MODEM by AUXport.

AWEI


6/21

Failure descriptionFailure description1.Checking port with show port command,physical port is UP and protocol is DOW N .

2. Checking port with show port command,physical port is UP and protocol is DOWN, butcan't ping other ends.

3. Checking port with show port command,physical port is UP and protocol is UP. But losingpackage seriously while data is excessive, and thisproblem often happens in the Ethernet port.

WEI


7/21

Whether the protocol is right

PPP X25 FR

Whether the working method is right

DCE DTE X25 FR

Whether the frame format of link layer is right

X25 FR Ethernet

Whether the address mapping of link layer is right?Whether IP address is right?

DDR X25 FR

WEI


8/21

Hello! Our

equipment may

have questions?

QUIDWAY 2501 router and CISCO routerperform PPP interconnection failure?

WEI


9/21

Two routers in terconnec t by DDN, and two endsencapsulate PPP protocol separate ly . Afterc he c king the por t s ta te w ith SHOW c o mm a nd,you'' l l f ind the physical layer and protocal layerare both UP, but pinging opposite end fai lure ,

w h y ?1Refresh port state with SHUT DOWNNO SHUT DOWN command,

then pinging opposite end;

2Observe debugging information with DEBUG PPP PACKET front, to

find both sides are in REQUEST state while routers of two sides

perform LCP negotiation.There maybe problems in middle link, at this

time you should check the state of middle transmission line.

AWEI


10/21

Question1 :Two connecting sides encapsulate X.25(or encapsulate LAPB directly),but

protocol is always in disconnection state.Open debugging front DEBUG X25 PACKET

and to find that one end sends SABM frame,while the other sends FRMR frame.This

repeats continuously.

Solut ions:This pheonomenon is becauseboth s ide are encapsulated in the samewo r k ing mo de (DTE o r DCE) , a nd c ha ng ingworking mode of one end wi l l make i t .

AWEI


11/21

Question 2: X25 can build virtual circuit, but

which will reset or clear continually during data

transmission.

Solution: This result may be caused by incorrectparameter setting of flow controling. If it is direct

connection of back to back, please check local

sending window receiving window is matching or

not; If it accesses to public grouping network, it is

necessary to consult right flow control parameterfrom network management section.

EI


12/21

Question 3:W hen configuring x.25 addressmapping, the system prompts that the addressoverlap.

Analysis:In the X.25 address mapping,one IPaddress can only be corresponded to one x121address. When an IP address is configured to twodiffent x121 address,conflicts will occur.

Solution:Use the command no x25 map ip to delete

olde address mappings and configure the addressmappings again.

AWEI


13/21

Question 1: Frame relay of Quidway2501 and Cisccan not connect.

Anlaysis: The encapsulation format ofQuidway2501 frame relay defaults IEIF, while

Cisco defaults Cisco; LMI of Quidway2501 defaultQ.933A, while Cisco defaults Cisco.

Solution: Change settings of two sides into identicalvalues, i.e. port setting of Quidway:

encapsulation fr ciscofr lmi-type cisco

WEI


14/21

Failure description:Ping host computer of other netwo

unsuccessfully

Malfunction locating

1. IP address setting problem

2. routing problem

WEI


15/21

Question: When configure firewall,configuring the followingcommand:Access-list normal 102 permit udp any202.38.160.1 0.0.0.0 neq rip, to find

interface with IP being 202.38.160.1(maskis three 255) still can receive RIP package.

WEI


16/21

Failure description:Dial port configured by router can't dial

Malfunction locating

1.Modem can't work properly2.Configuration of dial port has error

AWEI


17/21

Not conf igure USER-NAME, which resu l t s in PPP

negotiat ion pass ing fa i lure;

N o t c o n f i g u r e P P P A U T H E N T I C A T I O N w h i c h r e sthat PPP don' t a sk for NAME from oppos i te end to

DDR appl ica t ion;

C o n f i g u r e d P P P A U T H E N T I C A T I O N P A P , b u t

c o n f i g u r a t i o n o f P P P P A P S E N T - U S E R N A M E h a s

error ,which results in PPP negotiat ion pass ing fa i lu

C o n f i g u r e d P P P A U T H E N T I C A T I O N C H A P , b u tc o nf ig ur a t io n o f PPP CHAP HOST ha s e r r o r , wh ic

in PPP negotiat ion pass ing fa i lure .

AWEI


18/21


19/21

Failure description

1.Check port by show port command, and Ethernealways keeps DOWN.

2.Check port by show port command, and Ethernealways keeps UP, but can't ping host addresssuccessfully.

WEI


20/21

Question:After dial user of 2509 dial router from asynchronous port(asy

port),you can ping asynchronous port and Ethernet port of 2509 at

terminal,but can't ping server on Ethernet connecting to 2509seccessfully.

AWEI


21/21

Analysis and solution for physical layer problem

Analysis and solution for link layer problem

Analysis and solution for network layer problem

Analysis and solution for DDR problem

Analysis and solution for Ethernet problem

WEI

sat12 trobule shootting

Documents