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1500 questions
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2 answers

SVI as a DHCP client

Can a Cisco switch be configured to have a management interface (or SVI, or VLAN interface) become a DHCP client, therefore obtaining its own IP address on the respective network? This is out of curiousity, as I have not been able to come across the…
eric
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2 answers

5 nines, how is it built from 4 nines links

How is 5 nines calculated using lesser reliable links? For example, we have 2 x 4 nines connections used in an active/active setup... which supposedly equates to 5 nines, but I don't buy it... how was a greater uptime achieved with lower…
user10021657
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7
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3 answers

Fiber between two sites - no signal lights

We need to have fiber connection between two sites (distance less than 300 meters from each other). Currently there is multi-mode fiber connected to old switches working nicely. Now we are updating our switches to 10Gb and trying to connect, but it…
lingo
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7
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1 answer

Configuring a Cisco ASA 5505 for routing

I'll start by pointig out that networking issues have always left me scratching my head. There is something about routing especially that I just haven't had that "Oh I get it" moment yet, so it's likely this is a very basic misconfiguration. I am…
Chris O'Kelly
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2 answers

Securing Cisco device from brute force attacks

I'm trying to block users from configuring a Cisco IOS device if they have entered incorrect passwords a number of times. This is the command I'm using: Router(config)# login block-for 120 attempts 3 within 60 Which should block login attempts for…
Axel Kennedal
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7
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1 answer

Juniper EX 3300 Incorrectly Identifies SFP+ Transceiver Module

We have 2 Juniper EX 3300 switches operating in a stack. It is running Junos 12.3R3.4. The switches have 4 SFP/SFP+ Ports. On FPC 1, PIC 1, Xcvr 0 you see a description of "SFP-FC8G-SW." However, the transceiver is a Juniper branded 10GE SFP+ SR…
sardean
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6 answers

What happens with a ping when it enters a network? Is the router the one answering with a reply?

What happens with a ping when it enters a network? Does the router redirects it to one of the devices on the network, or it sends the reply itself? Device a1 from network A, with public IP adress P1 sends a ping to a public IP on network B, with IP…
Alex M.M.
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2 answers

OSPF on ASA 8.2 not advertising /32

We have set up OSPF between our 2 ASA 5540 running in Active/Passive and our Internet provider's Juniper routers. We would like to advertise routes based on the content of an ACL through a route-map : router ospf 1 router-id X.X.X.A network X.X.X.B…
simsaull
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7
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3 answers

what is difference between MSS and Window Size?

What is actual difference b/w these two? 1) I have gone through many tutorials on Youtube where some have told that Window Size is what total packet size it can receive eg Window Size is 15000 bytes and MSS is what maximum packet size can be sent…
shivaniverma6991
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7
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1 answer

Using a Cisco router as an L2TP client?

I have a customer that for various reasons has a Cisco router sitting behind a NATed ADSL connection. They want to create a VPN to one of our points of presence and the only options we offer are site to site or L2TP dial in. Is it possible to…
atp
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1 answer

What are some workarounds / fixes for UTM/IDP on Junos 12.1X44-D10.4 for SRX Series branch devices?

The JNCIP / JNCIE-SEC latest courses use 12.1X44-D10.4 as the recommended Junos version. I setup a 30-day evaluation on my home SRX device to study JIPS, based on 12.1. At this point, I'm guessing that my problem is that trial licenses for…
lunistorvalds
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7
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1 answer

Ipsec vpn, phase 2 unable to come up

I'm pretty sure I know the answer to this but I don't know how to implement it. Trying to setup an ipsec vpn from a Cisco 2811 to a linux box running openswan. So far I can get phase 1 up but phase 2 is having an issue. Its 100% a configuration…
TheEditor
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7
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1 answer

VTP V3 Cisco Switch Error when creating new VLAN

While trying to create a new VLAN on a switch stack (that has many VLANs and many interconnected switches) I get an error about the switch not being the primary server for VLAN database. When running the exec command "show VTP status" the switch…
Ejoso
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7
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1 answer

Why does export/import policy addition/removal cause a BGP session reset?

I was adding a new policy to both import and export list for BGP. Then I observed a bgp session reset. Can anyone explain this for me? The only change I made was to prepend a new policy to reject everything advertised from the neighbor and advertise…
Bo Cao
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7
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2 answers

What precisely is a link?

When reading about layer 2 the word "link" is frequently used but strangely I'm struggling to find a formal definition of it. What is the precise definition of a link? So in the image below, how many links are in this network and what makes that the…
Isaac
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