VTP Mode, Network Command in OSPF, & AutoNegotiate

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3 more questions:

1. Once I configured the appropriate information in switch 1 (such as VLANs) to be used as updates to switch 2 while on vtp mode server, does switch 1 need to have its configuration saved in startup config in order for the changes & vtp updates to take place in switch 2?

2. If I issue a Network command for OSPF with network 192.168.2.1 wildcard 0.0.0.0 (that ip address is connecting out of a router's fast Ethernet port) or network 192.168.2.0 wildcard 0.0.0.3 (representing 3 computers for that network), does the neighboring router still accept either update?

3. If one switch has it's speed & duplex hard coded (speed 100 duplex full), does the connecting switch set to autonegotiate receive its info at half duplex? Or does it receive it's duplex if both are set to autonegotiate?

Thanks

@Ponciana-S-Pajela said:

3 more questions:

1. Once I configured the appropriate information in switch 1 (such as VLANs) to be used as updates to switch 2 while on vtp mode server, does switch 1 need to have its configuration saved in startup config in order for the changes & vtp updates to take place in switch 2?

Nope, once you have VTP configured and ready: vtp mode server and vtp domain-name CCNA and vtp password ICND2 They will start to send vtp traffic and setup if you've configured trunking between the switches. It's always a great idea to save your configs but it's not a requirement...just a great thing to do as a habit.

2. If I issue a Network command for OSPF with network 192.168.2.1 wildcard 0.0.0.0 (that ip address is connecting out of a router's fast Ethernet port) or network 192.168.2.0 wildcard 0.0.0.3 (representing 3 computers for that network), does the neighboring router still accept either update?

Yes, it will allow you to do both. Remember that OSPF is a classless routing protocol. So both will be accepted.

3. If one switch has it's speed & duplex hard coded (speed 100 duplex full), does the connecting switch set to autonegotiate receive its info at half duplex? Or does it receive it's duplex if both are set to autonegotiate?

Usually what happens here is that the switch is ready for an source or destination device to be at the end of the switchlink. Most source or destination devices will be set to send at full duplex...so the switch will auto to FULL. Usually, if you're connecting to another connectivity device (router or switch) then you want to hard set the duplex to do what you want it do on both side. Autonegotiation between infrastructure devices is for wimps!!! (just joking)... it's a best practice. It is a troubleshooting practice and for me used ("turn of the century") a best practice that is no longer.

If one is hardset, the other is set to auto. It will match duplex with the other hardset side.
if auto on both side, (I just tested this on two routers) then it will negotiation to half-duplex to insure that traffic can be sent. this is something that both switches without knowing what the other is thinking can safely send and know that it will work.

Thanks
Thanks for the great questions!

Cordially,
Ronnie Wong
Host, ITProTV

Nope, once you have VTP configured and ready: vtp mode server and vtp domain-name CCNA and vtp password ICND2 They will start to send vtp traffic and setup if you've configured trunking between the switches. It's always a great idea to save your configs but it's not a requirement...just a great thing to do as a habit.

Does vtp mode server, vtp domain-name CCNA, and vtp password icnd2 have to be configured on both switches?

In the early days of autonegotiation, there were some interoperability issues caused by different interpretations of the standard, so the recommendation at the time was to hard set speed and duplex on both ends of critical connections. But that was fixed by the turn of the century, so the recommendation today is to use autonegotiation everywhere. I think it is required for gigabit Ethernet. For 10/100 links, if one end is hard set and the other is autonegotiate, the autonegotiate end will correctly detect the speed (10 or 100) from the link pulses, but it can't detect the duplex so will use half duplex in order to be compatible with hubs that can't autonegotiate (though rare today, they were the norm back when the standard was first written). If the hard set end is configured for full duplex, there will be a duplex mismatch which will severely degrade performance. If you ever see a port reporting "late collisions", this is probably the cause. (Full duplex ports don't have collisions!)

@Ponciana-S-Pajela,

On switches in your VTP domain, you have to match on the following:

VTP Password incd2
VTP domain-name CCNA

They do not have to match on VTP mode.

Cordially,
Ronnie Wong
Host, ITProTV

@Rick-Sidwell said:

But that was fixed by the turn of the century, so the recommendation today is to use autonegotiation everywhere. I think it is required for gigabit Ethernet.

Figures....."turn of the century" yep that describes me! ;)

Cordially,
Ronnie Wong
Host, ITProTV