Things to pay attention to when the POS interface is interconnected with the peer router, especially the CISCO router, otherwise the router may not be able to communicate with the peer.
1. The POS interface of our NE router supports scrambling of line codes. By default, the POS interface of the router allows line scrambling, that is, Posscramble-atm is the default configuration, but the POS interface of a CISCO router does not allow line scrambling by default. . Note that the routers at both ends should be configured in the same scrambling mode, otherwise they cannot communicate with each other.
2. If the line adopts scrambling and scrambling, the default value of C2 (channel load) is 0X16 (comply with the definition of RFC2615, NE adopts this method); if the scrambling method is not used, the value of C2 (channel load) is 0XCF ( Comply with the definition of RFC2615, CISCO adopts this method). In the process of intercommunicating with the POS port of the peer router, attention should be paid to judging whether the line adopts scrambling. To allow line scrambling, use the command: posscramble-atm, and to disable line scrambling, use no pos scramble-atm
3. Setting the CRC value under the POS interface The
default setting of the CRC value is 32, and the default value of CISCO is 16.
Note: The CRC values at both ends must be consistent, otherwise they cannot communicate.
4. CLOCK clock setting
The default clock of NetEngine is the line (line clock) clock. When two NE routers are connected back to back using POS ports, the clock of one NE should be set to internal (internal clock) and the other should be set to It is the line clock, otherwise they cannot communicate with each other. Note that in actual deployment, the POS interface of the NE router usually uses the Line clock.
5. The interface mtu is worth setting
The default value of the NE router POS port mtu value is 1500. The default value of the CISCO router POS port is 4096. When the mtu values at both ends are inconsistent, it will be normal when the PING packet is small, and no packet loss will occur, but the PING packet is large. This will obviously drop packets. When this happens, consider whether the mtu value of the CISCO router is inconsistent with the mtu value of the router. If not, set the mtu value at one end of the CISCO router to 1500.
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