Wassim

show | redirect to display cisco.txt file on console: show | tee The output is displayed then redirected to file cisco.int.txt: show cpu processes cpu history : the following 3 screenshots. show processes config replace – I changed the hostname on ASW1. The change is seen on the running-conf and not on the startup-conf. – we want to rollback changes, i.e. restore the original hostname by restoring the startup-config. The latter resides on the NVRAM: we perform the rollback with “list” option, to see the changes. We see that hostname is back to ASW1:

I didn’t know that Cisco incorporated IPv6 and RIPng into its CCNA courses until now! that demonstrates that Cisco is keeping the value of its certs high in the market. I’m proud to be studying networking in general, and Cisco in particular. Showing RIPng configuration information show ipv6 protocols We can see which interfaces are participating in RIPng show ipv6 rip RIP_ZONE displays various information about the RIP_ZONE process Debugging RIPng debug ipv6 rip – see that link local addresses are used in multicasting – destination address is multicast FF02::9 ———– In my home TSHOOT lab, R4 has only fa0/0 in RIPng. – The split horizon rule is a loop avoidance technique that prevents a route from being advertised out the interface through which it was learned. Route redistribution into RIPng We’ll configure it on router R4, because here it is the ASBR between OSPFv3 and RIPng. We chose metric 10 because Seed metrics shoul...

Just like you wear a watch to have time, network devices have a time protocol called NTP that does just that. The following are my study notes on the subject. There are two types of clocks: hardware clock and software clock. The hardware clock has its own battery. When router shuts down, hardware calendar still works. When we reboot router, the software clock synchronizes with hardware clock, even if we already set the software clock. Once the software clock is user-defined, we can synchronize the hardware clock with it, with “clock update-calendar”. with “show clock” and “show clock detail”, if an asterisk is displayed then the time server is not authoritative which means that it is not reliable. The protocol has a notion of stata . Each time server has a stratum: Server with stratum 0 has more precise time than server with stratum 1, etc. Server with stratum 1 feeds server with stratum 2, which feeds server with stratum 3, etc. NTP synchronises sof...

We learn in this post how to configure route redistribution between OSPF, EIGRP, BGP and static routes. The first section depicts OSPF route redistribution into EIGRP. The second section gives an example of redistributing static routes into EIGRP. And lastly we see an example of redistributing BGP into OSPF. Injecting OSPF prefixes into EIGRP – On the ASBR, and after redistribution, there’s a change in EIGRP topology table. But no changes happen in the routing table: before redistribution: after redistribution: The change happens on the other routers, i.e. DSW1 and DSW2. Redistribute ospf match internal Before this command, here’s DSW1 RIB: Then: The 10.1.1.8 prefix is a subnet that’s internal to OSPF, i.e. it was not redistributed into OSPF before arriving to R4. The 0.0.0.0/0 is also an OSPF Internal route (the default route that’s injected by R3 into the totally stub NSSA) . So it is redistributed into EIGRP too. “redistribute ospf ..”, wit...