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1500 questions
9
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2 answers

Voice VLAN information

I am aware of the ability to show the access VLAN assigned to an interface on a cisco switch. How about showing specifically the voice VLAN an interface is assigned? #show run int fa1/47 interface FastEthernet1/47 description Data&Voice switchport…
eric
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1 answer

What is the use-case of including the IPv4 address in IPv6 address?

It is possible to include the IPv4 address into IPv6 address. For example, 2001:db8::c0a8:6301 where last 32 bits are IPv4 address 192.168.99.1. There is even a special notation of IPv6 address where last 32 bits are in dot-decimal notation. Example…
Martin
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9
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2 answers

How to control unwanted UDP traffic (Broadcast & Multicast) on Cisco Router 2911?

Please suggest, we are getting UDP traffic either broadcast or multicast in router 2911 which cause 95%+ utilisation of the router. And we got error in link and business impact due to this. Company has stock exchange business and nano sec downtime…
Varun Luthra
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1 answer

NAT VLANs with same IP Subnets

I have a VMware environment in which VMs are running a simulation suite. The software used has hardcoded IP addresses, about 10-15 VMs, and we are running multiple instances of this software each in different distributed port groups. So SIM1 VM set…
umhelp
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9
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6 answers

Do network adapters read incoming bits in a single stream?

When a Gigabit network adapter is receiving data, how is it receiving the bits? Is it seeing it all in one stream of 0's and 1's? Or is there somehow multiple streams of 0's and 1's coming in at the same time? For example... let's say there's two…
shihku7
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9
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3 answers

Is there a performance difference between a managed an unmanaged network switch?

Is there a tangible difference in speed/latency between a managed and unmanaged network switch?
Mining15
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9
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1 answer

How to run redundant BGP via Quagga on /30 netblock?

My new BGP upstream has allocated a IPv4 /30 netblock as the glue block for connecting our routers. I however want to run two routers, and failover between them. If the netblock was larger (/29), I could easily run BGP sessions from both of my…
robbat2
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1 answer

Summarized OSPF routes advertised?

Preparing for CCNP, doing some lab work. ZEUS is summarizing two loopbacks with area 2 range 172.16.2.0 255.255.254.0, and the summary route is arriving on router 'WODAN' but the subordinate routes (2 /32's) are also still showing up in WODAN's ip…
A L
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9
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5 answers

Do routers change MAC address of packets when forwarding

Lets say host A wants to send a packet to host B through R1(interface 1 then 2) and R2 (interface 3), so my questions is: When the packet is forwarded inside R1 (from interface 1 to interface 2), ready to be sent to R2, does the pack's source…
amjad
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9
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2 answers

Where is Ping's "round-trip time" stored in the IP header?

If we use ICMP's ping, we know the TTL and round-trip time are stored in the IP header. In the below IP header map we know TTL's location, but where is the round-trip time? Is it stored in Options?
aircraft
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9
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3 answers

What is the difference between a VRF and VRF-Lite?

To the best of my knowledge, the concept of VRF is something that exists only in the Cisco World. Other vendors refer to this concept as VPN, which is in other words, a way to keep routing tables separated within a router. Knowing that what is the…
gaetano
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9
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2 answers

How does NAT work with incoming UDP packets from unknown IP

Apologies in advance for the relatively noob question and if this is off topic here ( I am not sure...) The situation is that I have a UDP client and server bound to the same port. My understanding of NAT is that UDP packets going out from the…
Sentinel
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1 answer

Diffrence between "wr" and "copy running config to startup config"

For saving configuration in Cisco devices we have "wr" and "copy running config to startup config" i am curious what is difference between these two command.
R1w
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9
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3 answers

How do VPN's forward network traffic? (Layer 3)

I am looking for some info on how VPN's (Virtual Private Network) forward network traffic through its VPS (Virtual Private Server). Take an example where you are connected to a VPN. You make a request to a website, which then makes its way down the…
cg14
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1 answer

Extra long ethernet, or similar technology, for kite

I just need to have a webcam and some equipment on a kite, running on Ethernet. But unfortunately the string will be more than 200 meters long so Ethernet will not work, (as far as I know). Transfer speed should be at least 10mbps. This is…
Prostitutor
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