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1500 questions
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2 answers

netstat -nr returning "0/1" -- what does that mean?

In exploring how my local openVPN virtual interface utun0 works, I came across the following data, and I don't know how to make sense of it. (I'm on a Mac) $ netstat -nr Routing tables Internet: Destination Gateway Flags …
Alexander Bird
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Error: `EIGRP is restricted to stub configurations only on this platform`

We just bought some new Cat4507R+E distribution switches. When we bought the switches, we asked for an Advanced Services K9 image, but our reseller told us they only come with a Universal K9 image. I didn't know better, so I said OK. However, when…
user2561
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VRFs, VLANs and subnets: difference

I have a basic understanding of VRFs, VLANs and subnets. I understand that VLANs operate on L2, and subnets and VRFs (lite) on L3. What I don't understand, is why you would choose one over the other when you mostly care about segmentation. Imagine…
Michael
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Translating SNMPWALK output into human-readable format

I am asking this question which is related to a question I previously asked and was comprehensively answered by @MikePennington. When I asked that question, I intended to know how to poll arp table from a switch, but in his answer, he included mac…
sosytee
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2 answers

Can I use Cisco Anyconnect with mobile devices?

I've got a lot of clients with mobile devices that want to connect to our corporate network which uses Cisco Anyconnect. How can my clients connect to our VPN using a mobile device?
Lucas Kauffman
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Cisco ASA: What is the "tx hangs" counter on show interface?

Consider the following output from show interface: Interface GigabitEthernet0/1 "inside", is up, line protocol is up Hardware is i82546GB rev03, BW 1000 Mbps, DLY 10 usec Full-Duplex(Full-duplex), 1000 Mbps(1000 Mbps) Input flow control is…
tunnelsup
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2 answers

Directed and Limited Broadcast confusion

Let's say I am on a network 192.168.1.X and I use the below ping commands. ping 255.255.255.255 ping 192.168.1.255 Why we are calling 1st one as limited and 2nd one as directed ? In what category does the below will come ? ping 10.X.X.X X is…
user2677679
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4 answers

Raw-Ethernet Frames

Recently I was puzzled by the following articles about Raw-Ethernet frames: RAW ethernet vs. UDP Message Passing Using Raw Ethernet Frames Briefly, both of them discusses that it is possible to establish a point-to-point communication using only the…
Mark Messa
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Port mirroring on an HP Switch (HP 2915-8G)

for sniffing purposes I need to mirror traffic on an HP 2915. How would I go about doing so?
Max
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12
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2 answers

Syslog message for CDP interface down

I have been searching for this for a while and haven't found one yet. I need a Cisco IOS command to send a syslog message or snmp trap whenever an interface that has a CDP neighbor goes down. Some people have told me just rely on routing protocol…
radio-free-europe
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What purpose is the Uplink port in layman's terms and do I need it?

I have an old Linksys switch (EZXS55W) and it has worked fine for many years now, but I tried to hook something up today to the last open port and noticed the device didn't work when I did this. When I looked about my switch, it says that it…
Vistance
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12
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3 answers

Identifying a Cisco access point post-install

We have about 50 Cisco 1242 access-points and we're managing them with a Cisco 4404 Wireless Lan controller. The guy who installed the APs did not assign a location to the access points in the controller. We are seeing some malicious behavior from…
Michael Teeman
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Tracing TCN Messages in STP

We have about 20 vlans on a L2 network running Rapid PVST+ where the root bridge is a stack of Cisco's 3750 switches. I am a bit puzzled by the number of TCN notifications I receive on the switch.. The 3750 stack is the root for all VLANs and it…
user209
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Site-to-Site VPN Tunnel Up Not Passing Traffic

I have a site-to-site VPN that seems to be dropping traffic from a particular subnet when a lot of data is being pushed through the tunnel. I have to run clear ipsec sa to get it going again. I notice the following when running show crypto ipsec sa.…
Rowell
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Do unused Cisco IOS features take up RAM/CPU resources?

For example, let's compare IP Base vs. Advanced Enterprise Services. Let's say you have advent installed, but you're only actually using the features relevant to ipbase. Other than flash memory space, would running advent when you only need ipbase…
WaxTrax
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