real ccna exam simulator
-
- 1485 Reviews
The route is normal, and all three routers can learn the route of the whole network. and so:
Initial database synchronization is performed before the adjacency is formed
Net 49.0001.0000.0000.0002.00
Outgoing tag or VC
The configuration of R2 is as follows:
Checksum: 0x6FEB Length: 132
Router-id 2.2.2.2
Ip address 10.1.23.3 255.255.255.0
If a router does not refresh its generated LSP after the LSP refresh interval , and the LSP remaining timer field has been reduced to 0 , all routers that have the LSP copy will copy the LSP from its own chain after the 60S grace period. Clear in the road state database. This 60S time is ZeroAgeLifetime , zero lifetime, and not configurable.
75M
404
Lists the list of directly connected IP address prefixes
!! OSPF cost of the interface
*Aug 18 09:06:07.919: Controlled Load Service break bit=0 service length=0
Hostname: R1 Router ID:
Domain-password
!
The attribute used to describe the physical link consists of 32 bits . Each bit can represent an attribute of the link (such as whether it is encrypted or not) or a managed policy. There is no specific syntax for this 32bits . Each bit can be set to the latter without moving it. The network designer can think of specifying a specific meaning for a particular bit as needed .
L
*Aug 18 09:06:02.699: 10.1.45.4 (Strict IPv4 Prefix, 8 bytes, /32)
Reservable Bandwidth[3]:
Kbps (Global) Priority: 7 7 Affinity: 0x0/0xFFFF
Interface eth0 0/0
Interface eth 0/0
PDU
LSR or LSAck
Use the lockdown keyword (note that the above configuration is configured in the TE tunnel port).
!
The LFIB table does not contain inbound interface information.
R2
Mpls traffic-eng router-id loopback0 mpls traffic-eng area 1
Start LSP ID : Start LSP ID . Indicates the first LSP ID of the LSP range described in the TLV field .
Interface fast0/0
!! Only one interface activates MPLS TE
No bgp default ipv4-unicast neighbor 2.2.2.2 remote-as 2345
i L2 2.2.2.0 [115/20] via 10.1.24.2, Serial0/0
Detailed concept
Ip cef
SNPA is equivalent to the Layer 2 address of NSAP or NET .
5.5.5.5
*Aug 18 09:06:07.919:
Consider in detail the details of the adjacency relationship establishment process:
IS-IS supports plain text and cipher text MD5 authentication. Let's make a small summary below:
Checksum: 0x6FEB Length: 132
C 1.1.1.0 is directly connected, Loopback0 2.0.0.0/24 is subnetted, 1 subnets
Ip access-list standard accept-ldp permit 1.1.1.1
ISO10589
R1#traceroute 4.4.4.4
Remote binding: tsr: 2.2.2.2:0, tag: imp-null tib entry: 3.3.3.3/32, rev 6
Flag position
But in the CSPF algorithm, there can only be one path for a destination. When there are many paths that satisfy the basic conditions (this rule can only be made if TE metric , bandwidth, and related attributes cannot be decided):
Mpls traffic-eng tunnels mpls label range 500 599
Local Circuit ID Local circuit ID is a link identifier. The identity of this circuit is assigned by the router that sent the Hello PDU and is unique on the interface of the router. At the other end of the point-to-point link , the local circuit ID in the Hello message may or may not be the same value.
Number of Links : 1
Label 14 OAM alarm tag
FIB
Router ospf 1
Network 10.1.23.2 0.0.0.0 area 0
10.1.34.4 10.1.45.4 10.1.45.5 5.5.5.5
When the forwarding adjacency feature is used, the tunnel end and the end must be in the same area, and the tunnel interfaces at both ends must be configured. That is, this must be a bidirectional tunnel, and both tunnel interfaces must activate forwarding adjacency.
Min unit = 0 bytes,max pkt size = 1500 bytes
102
*Aug 18 11:26:02.546:
10.1.23.0/24
Ip cef
Peak rate
Moreover, it is not necessary to maintain the matching time of both parties when establishing the adjacency relationship.
RFC2966 standardized from Level2 to Level1 leaked routes
Interface
It is found that a targeted session is established between R1-R3 . Now, let's come back to the Fa1/0 port of shutdown R1 .
R4.00-00
No frame-relay inverse-arp
The maximum bandwidth is the total bandwidth of the link. In CISCO IOS , this value matches the physical link or the configured bandwidth value.
IS-IS and OSPF
In area 49.0001, we can see that all routers flood their own LSPs . LSPs are represented by LSPIDs , such as R1.00-00 . This R1 is the hostname of the device . Here we have the default hostname mapping mechanism. See above. . In addition , 00 after R1 is a pseudo node identifier, and 00 means that the originating router of the LSP is not a DIS , and then the last 00 is a fragmentation flag.
Type-10 Opaque Link Area Link States (Area 0)
Bytes tag switched
Affinity: 0x00000000
BoS
Interface
R1(config)#interface fa0/0
2
Is-type level-2-only
668
lab environment
In general, any router that checks for a corrupted LSP will be corrupted by sending a remaining lifetime to 0 .
PSNP (partial serial number PDU )
Neighbor discovery is performed by means of the Hello packet of UDP . The source and destination port of this Hello packet are both UDP646 .
Solution: R1 and R4 use the loopback interface to establish IBGP neighbor relationships.
We can verify it:
1174
FastEthernet1 / 0, Src IP addr: 10.1.13.3 Addresses bound to peer LDP Ident:
Also called a pseudonode, it is a virtual router in a broadcast multi-access network, created by DIS.
Related standards:
When forwarding, if the destination address is present in the area within,real ccna exam simulator, the direct use of L1 LSDB routes generated forward packets, if the destination address is not in the region, the use of this area nearest L1 / L2router as an outlet outside the area network, whereby May cause sub-optimal routing
basic configuration
102
!
Interface Ethernet0/0
In the mechanism implemented by MPLS TE , the head end router of an LSP can learn the topology of the network, and can calculate the optimal route that traverses the network to reach the router at the end of the LSP (not only the metric but also the bandwidth and chain. Road attributes and other elements).
The configuration of R2 is similar, so that in the TLV used for authentication in the IIH , the ciphertext after the hash is loaded, and the password is not exposed.
Router isis
Type : 0x0800 carries IPv4 packets and finds FIB.
Establish mapping of data link layer address to network layer address ( CLNP address)
Run OSPF on the entire network to announce direct connection and loopback interface.
7
Complete MPLS TE configuration on R1 .
1.0.0.0/32 is subnetted, 1 subnets
Explicit_route
Regional prefix replacement. As shown above, you want to replace the original area prefix 49.0001 with 49.0002 . To achieve this goal, configure an NSAP address for the new area prefix on A and B. Note that the SystemIDs of the two addresses must be the same. Then delete the areas of A and B in turn .
The link between R4-R6 and R5-R6 has a bandwidth of only 20M , which obviously does not meet the requirements. Therefore, R1 will only consider the following links:
75000
*Aug 18 11:26:02.546:
The flooding of LSPs means that when a router reports its own LSPs to neighboring routers , the neighboring routers transmit the same LSPs to its neighboring routers, and then LSPs are transmitted to the entire hierarchy. One way inside. Through this "flooding", each router in the entire hierarchy can have the same LSP information and keep the LSDB synchronized. Each LSP has its own 4- byte serial number. The sequence number of the first LSP sent by the router is 1. When the new LSP needs to be generated , the sequence number of the new LSP is incremented by 1 on the previous LSP sequence number . A higher serial number means an updated LSP .
