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What was the intended use for VLANs 1002, 1003, 1004, 1005? (fddi trcrf fddinet trbrf)

The output of show vlan brief includes VLANs 1002 - 1005: 1002 fddi-default active 1003 trcrf-default active 1004 fddinet-default active 1005 trbrf-default active…
jester
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Expanding an HP IRF topology

I'm examining options for a future expansion of our infrastructure. We rent space at a colo so we don't have a dedicated datacenter of our own. This means that our next major expansion will likely involve two discrete cages not immediately adjacent.…
Blue Warrior NFB
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How OSPF decides a network to be a stub network?

In RFC 2328 it mentions that link-state information of all Loopback interfaces and all interfaces with network mask as /32 (host ip addresses) are advertised as stub network type. Now what about the cases where a interface with /24 mask is connected…
Hemanth
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Which VLANs are allowed on this trunk?

I'm getting some mixed signals when configuring a trunk on a Cisco switch and I'd like to know which VLANs are actually being allowed on it. The way I want it to be is that only VLANs 1,10,20,30,99 should be allowed. Have a look at the…
Axel Kennedal
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If TCP packets are pre acknowledged, what happens if packets are dropped?

On a VSat link with 800ms RTT latency and 10mbps bandwidth, that means 1MB bandwidth-delay product (data in flight). According to this useful (but closed) Q/A, packets are injected on both sides of the TCP connection to acknowledge the packets…
Kind Contributor
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How is IEEE 802.1ad (aka VLAN Tagging, QinQ) valid, when the packets are too large?

Recently i've been dealing with MTU issues. And it all seems to stem from the fact that the ethernet adapter on newer computers default of a frame size of 1504 bytes: >netsh interface ipv4 show subinterfaces MTU MediaSenseState Bytes In …
Ian Boyd
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Why does 1000BASE-T need Auto-MDIX?

A 100BASE-TX PC interface sends out its frames on pins 1,2 and receives frames on pins 3,6. If we connect this PC's NIC with that of another PC we cannot use a straightout cable, because the frames sent by the first PC would arrive on pins 1,2 of…
Marcos Gonzalez
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Wireless Controller based vs Non-controller based

I am looking at upgrading our wireless infrastructure from 60+ SOHO access points to an Enterprise level solution. We are currently testing Ubiquity (have 12 in our most dense areas) and it seems to be doing exactly what we need it to do, but from…
AWippler
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ARP Replies can they be Broadcast

I have been informed by certain networking professionals that ARP replies can and sometimes actually are broadcast packets instead of unicast. If and when would you use a broadcast ARP reply?
mlebeter
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Single Access Point vs. Multiple Access Points

Vague Question: If one access point can do the job adequately is there still an advantage to using more than one? Scenario: 1 access point at the center of your network required coverage area should adequately cover the area. There will always be…
David O'Brien
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Cisco 7600 q-in-q functionality on a Cisco 6500

Is it possible to make my existing 6509 switch function as a 7600 router? Even if it means purchasing a new sup or other inline card. I need certain router features, such as q-in-q tag termination. We need to terminate q-in-q tags from wholesale…
rick
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What is the name of the feature of a Router that prompts a user with a webpage when connecting to network?

The context of this question is for a customer WiFi installation at retail locations. What I want to achieve is that when a user connects to the network for the first time, a webpage is opened on their device asking them to log in with account (i.e.…
cml
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FQDN's in crypto maps and AAA servers possible with dynamic DNS resolution? Cisco ASA

Can I use FQDN's in crypto maps when setting a peer (where I'd normally use an IP), and can I use FQDN's when defining an LDAP Server or any other AAA Server in a server group? In both cases the FQDN's would have to be resolved by calls to an…
A L
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Is there an SNMP MIB for Cisco Track Objects

My goal is to write a service check that pulls the status of a Cisco track list that is performing a Boolean OR. I have a screen scraper in place currently, but that is really not ideal in terms of scaling this type of service check. The track…
one.time
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Arista MLAG ISSU upgrade - primary/secondary switch?

When upgrading Arista switches which are part of an MLAG cluster, is it necessary to start with the secondary switch? In "Arista Warrior", from Gary A. Donahue, he specifies on page 123 to start by upgrading the secondary switch. But there is…
Benjamin A.
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