z**r
发帖数: 17771 | 1 看到一个文档，说在做BGP RR的时候，如果IGP是ISIS，并且interface MTU不是使用
default MTU，那么推荐使用clns mtu 1497.
有人明白为啥是1497而不是更大或者更小？ | f*******8
发帖数: 3612 | 2 版主啊，咱们这个版是不是也应该把datacenter收拢进来。
【在 z**r 的大作中提到】
: 看到一个文档，说在做BGP RR的时候，如果IGP是ISIS，并且interface MTU不是使用
: default MTU，那么推荐使用clns mtu 1497.
: 有人明白为啥是1497而不是更大或者更小？
| s*****g
发帖数: 1055 | 3 My thought:
ISIS transport uses 802.3 LLC, which has 3 extra bytes in the frame, this 3 bytes in
Ethernet II is used for data, EthernetII interface can accommodate 1500
bytes data which is typical interface MTU, so when it comes to CLNS/ISIS,
you want to make CLNS MTU to be 1500 - 3, which will be 1497. For other
flavors of interfaces which have larger interface MTU, you still want to set
to lower CLNS MTU 1497 such that LSPs won't be fragmented during flooding
from one flavor of interface to other flavors of interfaces. If Ethernet
jumbo frame is supported across the network, I don't think the
recommendation is still valid.
You want the MTU size to be as large as possible so one ISIS update can include
as many TLVs.
How does this have anything to do with BGP RR? only thing related is you typically set ISIS overload bit on RR,
but that has nothing to do with MTU.
【在 z**r 的大作中提到】
: 看到一个文档，说在做BGP RR的时候，如果IGP是ISIS，并且interface MTU不是使用
: default MTU，那么推荐使用clns mtu 1497.
: 有人明白为啥是1497而不是更大或者更小？
| z**r
发帖数: 17771 | 4 有道理，多谢
3 bytes in
set
【在 s*****g 的大作中提到】
: My thought:
: ISIS transport uses 802.3 LLC, which has 3 extra bytes in the frame, this 3 bytes in
: Ethernet II is used for data, EthernetII interface can accommodate 1500
: bytes data which is typical interface MTU, so when it comes to CLNS/ISIS,
: you want to make CLNS MTU to be 1500 - 3, which will be 1497. For other
: flavors of interfaces which have larger interface MTU, you still want to set
: to lower CLNS MTU 1497 such that LSPs won't be fragmented during flooding
: from one flavor of interface to other flavors of interfaces. If Ethernet
: jumbo frame is supported across the network, I don't think the
: recommendation is still valid.
| z**r
发帖数: 17771 | 5 本来就应该有的，dcn现在很hot，没理由不讨论，呵呵
【在 f*******8 的大作中提到】
: 版主啊，咱们这个版是不是也应该把datacenter收拢进来。
| f*******8
发帖数: 3612 | 6 你对项目管理怎么看，最近发现项目经理很重要。
我们这个小公司，我觉得乱在人们理不清一个一个小项目
之间的依赖关系。
让一群不同心思的人在一起，把一个项目做成，很有意思的过程。
【在 z**r 的大作中提到】
: 本来就应该有的，dcn现在很hot，没理由不讨论，呵呵
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