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1500 questions
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1 answer

Private-vlan configuration - connectivity issue

I've an issue leading with Private Vlans. I've fiber modem and they can't reach the DHCP/TFTP to be provision. I suspect from the configuration of Private VLANs. Can you review them ? My doubts are mainly on access switch and trunk configuration on…
cgasp
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Does a wireless access point has a role between two wireless devices?

When I send packets to another computer (both computers have wi-fi) is the AP required to communicate or can the other machine receive the information directly from my computer without the AP?
BrunoMCBraga
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How are multiple SSID's handled on same access point?

In case of multiple SSID's on some AP, how is the information forwarded? I mean, the simplest AP's have just one wireless interface so its basically receiving trough one antenna and send it trough the same antenna which does not make much sense to…
BrunoMCBraga
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Is ethernet a term describing just the protocol or the interfaces also?

Is ethernet describing the protocol and therefore cat5 cables became labelled ethernet cables because they are used for this protocol?
Simon
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DHCP Snooping Confusion

I'm trying to work out how to enable dhcp snooping and dynamic arp inspection on our guest network and I'm a little confused.... Here's the situation: We have a hub and spoke topology, with a main core switch connecting to multiple layer…
Alicia
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Why do I get "% Warning: use /31 mask on non point-to-point interface cautiously" when I use a /31 subnet mask?

Why do I get % Warning: use /31 mask on non point-to-point interface cautiously when I use a /31 subnet mask over Ethernet, and why am I not able to ping from R1 to R2 when both the interfaces have accepted the /31 subnet mask and they both are…
Heisenberg
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1 answer

Staging Many Lightweight Cisco AP's for Deployment

My organization is soon going to be deploying approximately 600 new Cisco 2602i access points in a CAPWAP deployment with several 5508 controllers. This is an infrastructure refresh; currently we have a mix of older Cisco AP's using CAPWAP with…
Brett Lykins
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8
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2 answers

IPv6 RA SLAAC prefix lifetime

From what I understand, there is no way to change the prefix lifetime once hosts install the prefix. If I shorten the valid/preferred timer for a prefix, it has no effect on hosts already using the prefix with SLAAC until the host tries to renew the…
sdaffa23fdsf
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1 answer

Cisco ASA - Delete or rename "names"

I had a bad experience with Cisco ASA when changing/renaming "nameif" interface attributes. I would like to know if renaming or simply deleting existing names used in ASA config will do any damage to the configuration.
laf
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4 answers

Advice for network & device configuration using Comcast Modem?

Summary My ultimate goal is to run a VPN through my Cisco Router, which to me means getting the Comcast Gateway out of the way. To this end, I would like to place my Cisco Router (and/or Switch) logically closer to the WAN and remove my Comcast…
Andrew Philips
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2 answers

carrier's vlan tags overlap my own

I have a 3 site network: one is a data center colo and the other two are offices. The new Metro Ethernet service we just installed requires the colo site's traffic destined to the offices to be in VLAN 10 or 20 depending on the…
longneck
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4 answers

discover duplex mismatch interfaces in the network

What are the causes of duplex mismatch other than misconfiguration? (power outage? improper cabling? auto negotiation implementation bugs?) Any thoughts on discovering duplex mismatch? NetMRI seems to use interface error rate. Is it sufficient to…
sdaffa23fdsf
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2 answers

ASA in multiple context: save config

I have an ASA running 9.0(1) with four security contexts. When we modify a context, our standard procedure is to do a "write mem" inside that context. But sometimes we have to modify all the contexts in the same change window. Can we just do a…
Nachos
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8
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1 answer

Wireshark Filter - OSPF Database Description Link State ID

Within Wireshark, how would one write a display filter for the IP address of the Link State ID within an OSPF Database Description packet? The Link State ID addresses are found within the LSA Header of the DB Description packet.
THE DOCTOR
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Native Vlan Cisco Catalyst and Layer 3 switch

I have run into an interesting issue setting the native VLAN between one of my Cisco Catalyst 2960 and my Layer 3 switch (third party). Here is the setup, the layer three switch is set up to run on native vlan 171 and allows vlans…
veel84
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