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So, now that you've had a few minutes to consider this topology and consider

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why, for example,

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a VM here couldn't connect to or get a ping response from this external gateway

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at 10 to

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220.0.1, let's talk about a few potential problems.

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Number one, at this device right here, maybe they're not allowing via the

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device itself.

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Maybe they've configured it to not be able to respond or not being willing to

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respond

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to a ping request.

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So, if this customer down here is trying to ping that IP address, maybe locally

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here

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at this router, it's configured to not respond to a ping.
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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at this router, it's configured to not respond to a ping.

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So, that is definitely a possibility.

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So, as far as testing that, we could also go ahead and do a ping, for example,

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from

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VM4 to the virtual IP address or to the edge IP address on that common 10 to

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220.0 network

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segment.

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So, if the ping worked from here to the IP address on the segment that the

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gateway owned, it

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could be an indication this router has been configured to not respond to ping

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requests.

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However, another option could be that this router right here didn't get the

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routing

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information that it needs.

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So, even though we configured BGP here, the customer did between the external
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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So, even though we configured BGP here, the customer did between the external

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router and

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the tier zero gateway, maybe this tier zero gateway forgot to do a

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redistribution of the

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routes down here, the 1010 and the 1020 networks at tier one.

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Perhaps it forgot to redistribute those into BGP and as a result, this external

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router

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has no clue from a routing perspective of how to route in the correct direction

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to get

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back down to the 1010 and the 1020 subnet.

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Another problem could be that these VMs here don't have a correct default

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gateway that

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leads off to their respective tier one gateways.

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So, if these IP addresses here on the segment 10, segment 20 are .1 on their
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So, if these IP addresses here on the segment 10, segment 20 are .1 on their

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respective subnets

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and the clients aren't using those as the correct default gateway, that could

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cause

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a problem.

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So, if the redistribution was configured correctly here at the tier zero

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gateway, perhaps these

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tier one gateways were not configured to correctly advertise those subnets and

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if they

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don't advertise them, then the tier zero gateway has nothing to redistribute

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into BGP.

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So, that could also be another challenge.

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So, as far as solutions that we could offer, one would be to verify the BGP

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between the

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router here and our tier zero gateway, just to verify that we have the
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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router here and our tier zero gateway, just to verify that we have the

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neighborhood, verify

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that we're advertising the routes that we expect to be, make sure that we're

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advertising

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the routes from the tier one up to the tier zero and making sure that our

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clients have

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an appropriate and correct default gateway for their communications on the

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network.

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So, thanks for joining me in this set of videos and in the skill regarding

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using border gateway

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protocol as a dynamic routing protocol between our tier zero gateways in NSX

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and the external

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network and the external router that's also running BGP.
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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network and the external router that's also running BGP.

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So, again, thanks for joining me and I'll see you in the next skill.

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Until then, I hope this has been informative and I'd like to thank you for

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viewing.

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[BLANK_AUDIO]