问题一：IS-IS协议配置注意事项：
1.
注意在每一个参加ISIS协议的端口上加入family iso，在lo0端口上作family iso address 49.0002.xxxx.xxxx.xxxx.00，
2.
注意一定要set protocols interface lo0.0把loopback加入进ISIS里去，默认情况下同时建立L1/L2 adjacency。
3.
还有注意建立一定的lo0的ipv4地址与iso地址的对应关系，如10.0.3.4à0010.0000.0034
4.
默认的lo0地址是ISIS passive interface
5.
ISIS只支持broadcast和p2p两种网络类型，所以如果pos接口封装fr并且为multipoint模式的话，是不能commit的，这一点要特别注意，即如果部署ISIS就不能用多点接口；
问题二：ISIS基本操作例题：
Your next assignment is to add IS-IS authentication according to the criteria listed next. You
should refer back to Figure 4.1 for topology details.
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Backbone area authenticates both hello and LSP exchanges using MD5 with a key value of jni.
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Area 49.0002 uses a plain text password of jnx for hello authentication only.
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No routing disruption can occur in the backbone when adding authentication.
[edit protocols isis]
lab@r5# set no-authentication-check
[edit protocols isis]
lab@r5# set level 2 authentication-type md5 authentication-key jni
[edit protocols isis]
lab@r5# set interface as1.0 hello-authentication-type md5
[edit protocols isis]
lab@r5# set interface as1.0 hello-authentication-key jni
[edit protocols isis]
lab@r5# set interface fe-0/0/0 hello-authentication-type simple
[edit protocols isis]
lab@r5# set interface fe-0/0/0 hello-authentication-key jnx
[edit protocols isis]
lab@r5# show
no-authentication-check;
level 2 {
authentication-key "$9$iqPQB1hSrv"; # SECRET-DATA
authentication-type md5; # SECRET-DATA
}
interface fe-0/0/0.0 {
hello-authentication-key "$9$VhsgJTQn6A0"; # SECRET-DATA
hello-authentication-type simple; # SECRET-DATA
level 2 disable;
}
interface fe-0/0/1.0 {
hello-authentication-key "$9$iqPQB1hclM"; # SECRET-DATA
hello-authentication-type simple; # SECRET-DATA
问题三：ISIS路由泄露问题以及路由汇总
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Leak level 2 loopback addresses into area 49.0003 and ensure optimal routing to these prefixes.
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Summarize area 49.0003 addresses into the backbone.
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Maintain connectivity between all router loopback addresses.
[edit policy-options policy-statement leak]
lab@r4# show
term 1 {
from {
protocol isis;
level 2;
route-filter 10.0.3.0/24 longer;
}
to level 1;
then accept;
}
term 2 {
from {
protocol direct;
route-filter 10.0.3.0/24 longer;
}
to level 1;
then accept;
}
[edit]
lab@r4# set protocols isis export leak
注意，如果没有term 2的话，那么r1/r2看到的就没有r4的loopback地址，因为r4的lo0地址是protocol direct，不是protocol isis，所以policy对r4的lo0地址不生效
关于ISIS路由汇总，一定要先创建protocol aggregate，然后set term 1 from protocol aggregate/to level 2，then accept发送汇总路由；set term 2 from protocol isis/level 1/to level 2, then reject拒绝掉细化路由，
问题四，一些汇总以及路由广播注意事项
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默认的isis export policy不会把level 1 external routes发送给isis backbone
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做汇总的时候要看一下是否把isis external route 10.0.5/24给deny掉了！！！
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默认JUNOS软件发送wide/narrow metric的路由，默认情况下只接受narrow metric的路由（narrow metric最大只能有metric=63）；建议：r1/r2 disable level 1 narrow metric，r3/r4 disable level 1和level 2的narrow metric，r5也disable level 2 metric
问题五，ISIS例题，特殊要点
To complete this section, you must perform the following tasks:
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Ensure that r2 cannot reach destinations outside of area 49.0003 while keeping all its IS-IS
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adjacencies up and without modifying its routing-options stanza.
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Configure r6 with a level 1 priority of 0.
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Ensure that r5 never generates a non-0 selector byte LSP for the 10.0.8.8/30 network.
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Configure the r3-r5 ATM link so that flooded LSPs are spaced at least 300 milliseconds apart.
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Set the level 1 preference in area 49.0001 to 155.
第一个要求，在r2上使用命令set protocols isis ignore-attached-bit
r6的DIS selection priority要求为0，r5不生成non-0 selector bye LSP表示的是r5也不能为Designated IS，这就难办了…..其实如果priority都是一样的话，就比MAC地址，只有MAC地址高的才会被选举为DIS，所以本题目solution就是手工指定r5的MAC地址set interface fe-0/0/0 mac 00.00.00.00.00.11
[edit protocols isis]
lab@r5# set interface at-0/2/1.35 lsp-interval 301，此外在r3上也要作相应设置
lab@r5 set protocols isis level 1 preference 155
注意：如果骨干网IGP为ISIS，并且不给出OSPF的配置，那就要做反向工程。set protocols ospf traceoptions flag hello detail/error detail，并run monitor traffic interface fe-0/3/3 detail看是否有密码
注意：在r6/r7分别运行isis-ospf的时候，如果给出了让让调节isis preference的话，作两台机器的双向redistribution要小心，r6或者r7有可能从ospf学到应该是从isis协议学到的default route，解决方法是r6/r7上set protocols ospf external-preference 159
注意：默认情况下isis protocol 不会将isis level 1 external route发到level 2 backbone，必须在L1/L2 router上用policy：
Set term 2 from protocols isis/level 1/external/，to level 2, then accept
注意：注意边界IGP的subnet，就是与ospf router或者rip router的直接连接的网段，一定要公布给isis level 2
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