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1500 questions
9
votes
2 answers
Differences and functions of type codes 0800 and 0806
What are the primary differences and functions (or applications) of type codes 0800 and 0806?
Through my own research, I found the 0800 was related to the 0800 to the IP/Layer 3 of the OSI model.
I also found the 0806 was related to the ARP…
beckah
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9
votes
2 answers
Why do IPv6 unique local addresses have to have a /48 prefix?
According to RFC 4193, unique local addresses will always have a prefix of FD00::/8.. but according to Wikipedia:
The block fd00::/8 is defined for /48 prefixes, formed by setting the forty least-significant bits of the prefix to a randomly…
Isaac
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9
votes
1 answer
ProCurve CPU at 100% for several minutes after reboot
I have been doing firmware upgrades in HP switches. Two different models have been upgraded:
ProCurve Switch 5406zl Intelligent Edge (J8697A): upgraded from K.15.06.0008 to K.15.12.0012
HP 2520-24G-PoE Switch (J9299A): upgraded from J.14.54 to…
Daniel Yuste Aroca
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9
votes
2 answers
Learned eBGP routes not distributed to iBGP neighbors
I have (in GNS3) three Cisco 3640s running 12.4(23) connected in series (R1 -> R2 -> R3).
R1 and R2 are eBGP peers, R2 and R3 are iBGP peers.
R1 advertises network 192.168.1.0/24. R2 receives this route, but does not advertise it to R3.
Shouldn't…
user1038451
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9
votes
3 answers
I have a single ethernet switch. Should I use spanning tree?
I have a single ethernet switch. Should I use spanning tree?
If there is a redundant link, definitely need to enable STP.
In a single switch, how is it possible to have a redundant link?
Any other possible scenarios?
Maha
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9
votes
2 answers
BGP Autonomous System Path Duplicate AS
Is it normal to see a path as such in my BGP update ?
12 34 33 2 2 45 331
As I can see from the path above, AS number "2" appears twice ! Is it normal ? Are they any scenarios that could have made this to happen ? Is it an anomaly ? If it's like…
user3066913
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9
votes
4 answers
Abstract language to describe network deployments?
Is there any more or less standard/spec that is, vendor neutral, for network configuration language? Say, a VPC with networks and virtual machines would become an XML or JSON file.
Something like,
J. Doe
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9
votes
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
- 512
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9
votes
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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9
votes
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
votes
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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- 2
9
votes
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
votes
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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9
votes
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
votes
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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