CCIE Troubleshooting Tips
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To troubleshoot, always first check by Pinging and Traceroute/Telnet. AFTER this basic approach follow these steps (step 1 to 6 in all cases, then depending on the question) 1.) show ip interface brief ! To check which interfaces are configured with ip addresses and whether t hey are up/down 2.) sh run interface Serial1/1 (example) ! Then to check detail configuration of interface 3.) sh run | section router ! To check all routing protocols 4.) sh run | include list|permit|deny|map|match |set ! to check all Filtering. VERY useful command. 5.) sh run | include ip route ! To check any static routes
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ccie Ts tips
Transcript of CCIE Troubleshooting Tips
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CCIE Troubleshooting Tips
To troubleshoot, always first check by Pinging and
Traceroute/Telnet. AFTER this basic approach follow these steps
(step 1 to 6 in all cases, then depending on the question)
1.) show ip interface brief ! To check which interfaces are configured with
ip addresses and whether they are up/down
2.) sh run interface Serial1/1 (example) ! Then to check detail configuration of
interface
3.) sh run | section router ! To check all routing protocols
4.) sh run | include list|permit|deny|map|match|set ! to check all Filtering.
VERY useful command.
5.) sh run | include ip route ! To check any static routes
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6) In IGPs check :
A.) NEIGHBORSHIP
B.) AUTHENTICATION
C.) NETWORK COMMANDS
D.) Any special configuration which may be creating problem.
7.) IF policy-map is configured (which you will find out by Command # 4) then run the
following command to check :
"show run | section policy-map"
"sh run | include interface|service" ! to find out what is it doing and where is
it applied.
8.) For MPLS check :
A.) show mpls ldp neighbor
B.) show mpls forwarding-table
C.) show ip vrf
D.) show run | sec ip vrf
E.) show ip bgp vpnv4 all
F.) sh ip route vrf
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ContC
-> Check for any ACL stopping router in creating LABELS for prefixes.
-> Check for RD values and check whether right RTs are imported and exported or
not.
-> Check for PE-CE IGP neighborship
-> Check for "PE-CE IGP" to BGP and BGP to "PE-CE IGP" redistribution
-> Check for PE to PE BGP vpnv4 neighborship.
-> in OSPF over MPLS, check for sham-link and any discontageous Areas.
9.) in IPv6 question check ip addressing on interfaces and
"ipv6 unicast-routing" command.
10.) ip IPv6 IGPs, route-ids are "IPv4 ADDRESSES", which MUST BE UNIQUE!!, check
that on all devices.
11.) show run | include interface|ipv6 ! To check all ipv6 configuration
12.) in PPP question check local database and password. Use :
sh run | include username|ppp|aaa|interface
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13.) in MULTICAST question use
"sh run | include multicast|pim|rp|interface|igmp" command to check proper
configuration
14.) in MSDP question use the above command AND "sh run | include msdp" to check
the configuration.
