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8

Cisco 2960 switches pull in cool air from the sides and exhaust to the rear. Depth-wise they are 1/3 to 1/2 rack-depth (depending on exact model switch and rack). This leaves you very few options. If you mount them unmodified backside of the rack just about the entire switch is in the hot zone. That will only be OK if you have cold airflow running on the ...


5

As an Information Assurance (IA) principle, the less unnecessary services running on a device, the lower the attack surface. To mitigate issues, proper configuration and patching levels are key. Changing ports is one of many elements you can do to lower the potential security risk. Cisco has an excellent guide for proper implementation of the HTTP/HTTPS ...


5

IPv6 doesn't use ARP. It uses Neighbor Discovery (ND), which uses ICMPv6. Proxy-arp was used for IPv4 networks where some devices had a wrong subnet mask. The proxy-arp feature on the router would reply to ARP requests for off-net addresses so that such clients would send their traffic to the router so it would actually act as a default gateway. In IPv6 you ...


5

It's not a router problem and it has nothing to do with the "Cisco world". You can host multiple websites on a single web server all on port 80 via a single ip address by using Host Headers (or the Linux equivalent).


4

He is absolutely correct. Netgear switches are crummy and cheap with low manageability and tiny packet buffers. You're trading capex for opex. Cisco SMB switches are essentially a small step up from Linksys. Catalyst are pricier, but if you want your network to work and be manageable you need something in that class. For a tech company, a network is ...


4

It appears that someone can't spell phoneproxy correctly when they typed it in setting it up. Regardless it's for CUCM's phone proxy feature on an ASDM firewall. See here: http://www.cisco.com/c/en/us/td/docs/security/asa/asa82/configuration/guide/config/unified_comm_phoneproxy.html Here's the gist of it: The Cisco Phone Proxy on the ASA bridges IP ...


4

I recently wrote an Ansible module that allows you to use SSH+SCP to transfer a file to Cisco IOS devices. One of the use cases is obviously transferring IOS images. It has some built-in checks like not transferring the file if it already exists and performing an MD5 comparison (original file to transferred file). The MD5 is CPU intensive on the router, ...


3

One potential problem with HTTPS is that lazy people (like me) may not set up a Kerberos certificate on the device to ensure that connections to it are secure. Your certificate would have to come from one of 3 sources: a commercial certificate authority like Verisign (expensive), setup your own CA using a Windows or Linux server (not that hard, but time ...


3

You can login directly in enable mode if your privilege level allows it. I am running asa916-k8.bin on 5510 The command is aaa authorization exec LOCAL auto-enable Ravi L


3

The purpose of load balancing is not for a scenario where there's just one AP. It's intended for a scenario with multiple APs. When you set up multiple APs, you always put them not-too-far from each other. You want the APs to overlap, a little, to be able to hop between APs. You don't want one APs signal to completely die out before getting into the next APs ...


3

Appreciating this is an old question, and that it's already been answered - I did trip across it while frustratedly trying to determine what the "real-world" performance of some second-hand routers off eBay would achieve, and Google kept bringing me here. As the accepted answer states - the Cisco data-sheets (notably this comparison of major router models) ...


3

Did you issue the following commands? Enable the HTTP server for ASDM http server enable Allow the management host(s) to access ASDM http management_host_ip mask interface_name After doing the above in configuration mode, access ASDM from Firefox browser (you need to have Java JRE and Java browser plugin installed) using the URL ...


3

As one of the previous answers states, you can use Policy Based Routing and set up a route map on your router. However, instead of using VLANs or Static IPs, you could use QoS Marking instead. This could be rolled out in a group policy to your Windows PCs, and the route map on your router could be configured to look out for a particular DSCP value to ...


3

Q: Can layer 2 switch ports be configured as VLAN trunk ports? A: Most certainly. VLAN's are a Layer 2 construct. Q: Do I have to set both ends of the trunk as a trunk? A: Yes. A few things to note: You need to make sure that both sides of the trunk have the encapsulation configured as 802.1Q. I can't give you specifics on how to configure the trunk on ...


3

With the strict hot/cold setup it seems like even if the airflow could be reversed leaving the switches at the back of the racks would have a negative impact since they would be sucking in air from the hot aisle in the datacenter. Based on the diagrams of the switch that I can see online it is not a full depth switch, so when mounted on the back side of the ...


3

In reverse order... Your routing table is actually correct. The L flag means that is the IP address local to the router on that link, while the C flag means that network is attached to the router on that link. The problem would be that your modem doesn't know that the 192.168.10.0 /24 network is reachable via 192.16.1.69, or doesn't have a NAT policy for ...


3

The key problem seems to be a missing bgp dmzlink-bw option under the address-family in the configuration. Let me, however, summarise my comments here: bgp dmzlink-bw under address-family. neighbor dmzlink-bw only enables advertisement of bandwidth to neighbours, whilebgp dmzlink-bw enables proportional load balancing itself. Running-config had bandwidth ...


2

One cheeky and simple way to do this is to use two switches rather than one. You could then uplink half of your devices to one switch and half on the other, and thereby double your total throughput. If you then require more outgoing throughput from a single server, you could bond the two interfaces with uplinks to both switches in your room. Just make sure ...


2

Even though the device supports it, Cisco by default uses what I call "compatibility mode" for AAA, where it limits the feature set to the "old model". Use the aaa new-model, then try again.


2

I dont think a wiring issue as it copy, and always fail at the end. Remove your antivirus to test out, as it look to me a scanning error


2

Unless it is absolutely necessary, which I doubt, running layer-2 over a WAN is a really bad idea. STP will require all sorts of tweaks to work correctly with the increased latency. You need to measure the latency and apply it to all the STP calculations. Broadcasts, multicasts, and unknown unicasts will need to travel end-to-end to every switch port in the ...


2

You are nmapping the cisco router, so you are checking the open cisco ports, not the open webserver ports behind it. If you nmap the webserver you'll find port 80 open.


2

This looks like TCP sync flooding attack. You need to find out the TCB numbers to be able to clear the sessions. The Transmission Control Block (TCB) is a transport protocol data structure (actually a set of structures in many operations systems) that holds all the information about a connection. The memory footprint of a single TCB depends on ...


2

When you have a stack of switches, you want to create a loop with the stacking cables. Port 2 on one switch connects to port 1 on the next switch. Continue that until the last switch which will connect back to the first switch. This creates a loop in the switch connections. When you lose one link in the loop, you will still have a continuous link between ...


2

The first icmp packet is fail because host sends ARP request. If the destination host MAC is already in ARP cahce the device is not send this request.


2

If it is OK for you to change the default gateway of your clients to fail-over, you just need to configure 192.168.10.236/24 on your VDSL router's LAN interface and connect it to your switch (note that if your are using DHCP, you should probably also disable the DHCP server in the VDSL router so you don't have two DHCP servers in the network).


2

Yes, on Cisco IOS there are a lot of built in debug commands. Most of these are pretty noisy and are disabled by default. If you want to debug what's going on with DHCP, SSH to the router and first issue the command: terminal monitor This will make sure that logging from the device is printed in your terminal. Next, to get onto the DHCP commands issue: ...


2

Sadly I don't know. If you are planning to put any iSCSI traffic on the N3064 update your question or add a comment because I know a lot about that. Intel X540 based NICs definitely work with the N3064 and have available VMware drivers and should fit in a 16 lane PCIe slot, of which the DL360 g7 should have two. Putting those QSFP ports to work is annoying ...


2

I'd use real or observed numbers... Likely 400 Watts per server (assuming sane RAM and disk configurations) and ~380 Watts for the switch. This is based on experience with the equipment in production and working in and around data centers. Plan for expansion and growth as well.


2

I would use 'debug ip packet' and trace the ICMP packets at the time you send the bursts. That would give you an idea of what was happening. More info here: Cisco Debugging And, I'll reprint the warnings from that site here: Enabling debugging can disrupt operation of the router when internetworks are experiencing high load conditions. Hence, if logging ...



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