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1500 questions
7
votes
2 answers
How are different phone/GSM operators connected with each other?
This might be a noob question, but I am having trouble finding an answer to it.
Let’s say I am a new GSM operator. How would I go about connecting my network and my subscribers to the rest of the world?
Is the internet being used in the background?…

Duje Lalic
- 73
- 3
7
votes
3 answers
HP 2920 - Can stack without stacking module?
Is it possible to stack HP 2920 switches via ethernet connections (without add-in stacking modules)? I've consulted several of the docs on HPs site but can't find a definitive answer. I have older switches that are stacked this way.

mwood
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7
votes
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
- 512
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7
votes
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
- 583
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- 11
7
votes
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
- 71
- 2
7
votes
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
- 173
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- 1
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7
votes
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
- 671
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7
votes
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
- 562
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- 9
- 18
7
votes
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.
- 173
- 1
- 6
7
votes
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
- 173
- 3
7
votes
2 answers
Is the first address in an IPv6 subnet assignable?
I am working in a lab and have configured a series of /125 subnets between routers. Lets ignore the best practice for this discussion of using /64 for everything.
When I assign fd00:f9a8:ffff::257 to an interface, there is no issue with the…

ACiD GRiM
- 73
- 4
7
votes
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
- 173
- 1
- 1
- 3
7
votes
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
- 73
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7
votes
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
- 413
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- 12
7
votes
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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