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1500 questions
9
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3 answers

Cisco Router config alternatives to Cisco SDM (i.e. no Java required)

We have an old Cisco 850 Series router hanging around here and happen to have a need for it temporarily until we get our new Palo-Alto into place. Now, after I reset it and try to pull up the configuration page at 10.10.10.1 as you would normally…
bgmCoder
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2 answers

Cisco IPSec Site-to-site VPN. Permit traffic if VPN is down

Bit of 'belt and braces' configuration planning. Background: We have a successful site-to-site VPN link to our remote datacenter. The remote 'protected' network is also the IP network range that is opened up through the firewall as Internet facing…
Rob Shepherd
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1 answer

What does bandwidth (digital) really mean?

Recently I came across a new kind of NIC capable of 400Gbps (It kind of blew my mind). Does it mean it's electric circuitry is capable of serializing/deserializing (SERDES) 400G bits per second of data onto a wire while maintaining a relativley…
manish ma
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9
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3 answers

How many stack cables would be needed if we want to stack two 3850 switches

How many stack cables would be needed if we want to stack two 3850 switches : We have one 3850 switch and planning to add one more. So my guess is only one Power & One data stack cable would be fine. Or please let me know if it is mandatory to…
shailendra harinkhede
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9
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3 answers

packet drop on 10gb/s interface

I have a certain number of packets dropped on my 10gb/s interface, on Cisco 6500 with Sup 720. You can see underneath the number of dropped packet within a minute, after I cleared the counters. We don't see any performance degradation, and none of…
user4262
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9
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5 answers

Cascading Switches. Will it affect performance?

I am really new to large scale networking and all I know is the basics. I will be doing a network for a huge workspace consisting of multiple offices. There will be a total of 308 Clients, with at least 12 clients per office. I am following this…
Aaron Alfonso
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9
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2 answers

Are IPv6 Wildcard Matches in Cisco IOS Possible?

Facebook is very clever with their IPv6 address scheme, but it got me thinking about ACLs and Is it possible to write a Cisco IOS IPv6 ACL that matches ? In IPv4 you could match a middle octet such as 10.xxx.10.xxx in order to hit any 'x' with…
John Spade - 'DaSpadeR'
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3 answers

Cisco can't connect to Juniper device via SSH - Invalid modulus length

I'm trying to connect from a Cisco 886VA to a Juniper EX2200 via SSH. The connection fails with the following messages on the Cisco: *Jan 17 09:51:20.823: SSH2 CLIENT 0: Server has chosen 2056 -bit dh keys *Jan 17 09:51:20.823: %SSH-3-INV_MOD:…
Sebastian Wiesinger
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9
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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
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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
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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
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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
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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
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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
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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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