8

This is what I think you're trying to ask: When I have a DHCP network but want a handful of hosts to have static IPs, is it best to reserve the IPs on my DHCP server or set static IPs on the hosts themselves? If that's your question, edit it and I'll take out this paragraph. The only benefit I see of configuring static IPs on select hosts themselves is that ...


7

Can communication to broadcast 224.0.0.1 be made to reach hosts outside of the local subnet? First, that is a multicast group, not a broadcast address. Next, the multicast address is in the Local Network Control Block (224.0.0.0/24), and multicasts sent to groups in that block are limited to the network on which they originate. So given the above example, ...


6

Fiber is not so expensive unless you are getting fleeced. Indeed, it can be cheaper than copper cabling. It's also the right solution to long runs. Given the installation costs, it's likewise foolish to install 5e rather than 6A at this date and into the future for copper. The cost of the cable is a tiny fraction of the cost to get it installed correctly. ...


5

A very quick (and therefore incomplete) answer: Assuming all of the inside stuff is on the same subnet the ICMP messages are switch2 saying "I don't need to be involved in this, talk to the firewall directly". What I've usually done for these situations is set up a transit subnet between the inside router (switch2) and the firewall so that switch2 can ...


5

In the scenario you describe, you should definitely be looking at multiple access points, preferrably dual band APs. While coverage may be sufficient, coverage alone is no longer the primary consideration when deploying a wirelss network. Client capacity, channel utilization, signal quality, and reliability are much more important and multiple access ...


5

An ACL is a good idea to block this sort of behavior. You should also filter out any source addresses not belonging to the IXP networks to prevent spoofing. RFC 2827 talks about this as well, although their focus is on DoS attacks. If you don't advertise the IXP networks to your ISP, then the return traffic will never come back to the IXP through you. So ...


5

Some network device architectures assume that most of your prefixes will be /64's. Check this column in Ivan Pepelnjak's blog for more info.


4

The biggest concern is likely to identify where your bottlenecks are going to be, in terms of route aggregation. The basic parameters are likely going to be: each subnet must be a /64 (dictated by IPv6), and you have a /60, /56, or /48 to play with. As others have said, a /48 gives you 64k subnets, but it's still easy to paint yourself into a corner if you ...


4

The switch has a built-in help function: ? xa-eng(config)# trunk 1-2 trk17 trunk Do not use any protocol to create or maintain the trunk. lacp Use IEEE 802.1ad Link Aggregation protocol. <cr>


4

There's a big difference between "allowed" vlans and "created" vlans. Very few (read: NONE) of the switches I'm aware of can handle 4095 vlans. Entering the equiv of vlan create 1-4095 (i.e. all vlans) will result in an error. switchport trunk allowed vlan 1-4095 is not the same as having all vlans on the switch -- just that the port will not filter any ...


4

IKE is (in massively simplified terms/practically explained) just a way of establishing an IPSec VPN tunnel, and IPSec VPN tunnels don't inherently support multicast. You can put a GRE tunnel inside of an IPSec VPN tunnel which will support multicast, and other non-IP Layer 3 protocols, like apple talk, IPX, and NHRP, which explains why DMVPN which uses ...


4

First, POE can be used on Ethernet cables at the full maximum cable length, which is 100m / 328ft (90m (295 ft) of solid "horizontal" cabling between the patch panel and the wall jack, plus 5 meters (16 ft) of stranded patch cable between each jack and the attached device). I guess your issue is not POE but the Ethernet max distance. Second, although ...


4

According to the documentation for Configuring Cisco StackWise Virtual The SVL link needs to be connected to the sup-module. StackWise Virtual Link (SVL) connections are established only through 10G or 40G uplink ports on the supervisor module. You cannot establish an SVL using a 10G port on one switch and a 40G port on the other switch. Please refer to ...


4

This is explained in the IPv6 Addressing Architecture RFC (RFC 2373) in section 2.2 which deals with text representation of addresses. This provides three conventions for representing IPv6 addresses. First: The preferred form is x:x:x:x:x:x:x:x, where the 'x's are the hexadecimal values of the eight 16-bit pieces of the address. Examples: FEDC:BA98:...


3

Theres advantages to both approaches. It's down to you to decide which is more relavent on your network. The advantage of setting on the device is that the devices can still talk to each other if the dhcp server goes down or if a rouge DHCP server shows up. The advantage of setting on the DHCP server is that you don't have to go round to every machine ...


3

NTP isn't particularly jitter-sensitive because it uses originate and transmit timestamps to keep track of delay. Ntp.org explains in detail how it keeps delay in check, but here's a snippet: Synchronizing a client to a network server consists of several packet exchanges where each exchange is a pair of request and reply. When sending out a request, ...


3

The double colon :: represents a string of consecutive zeros. So it expands to: 1001:0000:0000:0000:0000:0000:0000:0001 The 64 should have been written with a slash as "/64" This is the subnet mask length, and works the same way as IPv4 (64 1's followed by 64 0's).


3

It does not matter, but leaving gaps between enumerated things, e.g. ACL lines, is a good practice, and people often carry that over to other things. You may want to leave room to add logically related VLANs to be in the same range of 10 to 19. For example, if you have department VLAN numbering, and a department that uses VLAN 10 for its data wants to add a ...


2

There are two interrelated issues here: coverage area and channel bandwidth/utilization. Multiple access points will extend the coverage area and improve throughput, because signals will be stronger and therefore your clients can operate at higher speeds. Even if your coverage is perfectly adequate with one AP, having multiple APs allow you to use ...


2

My personal experience is that we use whatever color matches the paint in the room its in, unless it is one of the following: Red: Hospital Monitoring Equipment Blue: Security Cameras Green: Any separate LAN or VLAN connection (ie. radiology has a few of these) I don't believe there is a specific standard for them. Correction: as Comments state below talk ...


2

IPv6 address space layout best practices I'm comfortable with IPv4 address space allocations. By which I mean: Given services to plan for, or an organization to network, I have a good grasp of how to plan IP address space usage. (or at least, I think I do. :) Are there any best practices guidance, or case studies, for IPv6 address space layout? Super ...


2

Edited answer: NTP should be placed in the EF class (same as real-time voice packets) according to the IETF's RFC 4594 Configuration Guidelines for DiffServ Service Classes. 5.2. Mapping for NTP From tests that were performed, indications are that precise time distribution requires a very low packet delay variation (jitter) transport. Therefore,...


2

You may consider the following general guidelines when implementing VLANs: Grouping devices by traffic patterns – Devices that communicate extensively between each other are good candidates to be grouped into a common VLAN. Grouping devices for security – It is often a good practice to put servers and key infrastructure in their own VLAN, isolating ...


2

I too recommend a Wireless survey. This avoids dead spots and other issues. With 2.4Ghz APs, you only have 3 clear channels that do not overlap. 5Ghz isn't so much of a problem. You might be able to get sufficient wireless coverage with 3 APs. Omni-directional antennas transmit like a bagel, Directly above and below aren't the best spot. Maybe two on ...


2

For point-to-point links, use a maximum size of /30. Depending on your model of router, it may support a subnet size of /31 which would be even better. Carve these small subnets out of your unused space. You can reserve a /24 network and use it only for p2p links, then take your smaller /30 /31 subnets from this space.


2

It depends on your device, if temperature is high, fans will spin faster and you reduce timelife of your switch. I think 63°C is slightly high but I have switches working at this temperature (or greater) with no problems. If you need a number, according N4000 manual, front led is triggered when "The thermal sensor’s system temperature threshold of 75°C has ...


2

Sounds like a definite mess. The solution is quite easy really: have an independent certifier check the installation, take the measurement protocols and hit the installer square on the head. There's no way this will pass.


2

So the question is kind of vague but there are some guiding principles worth considering: Separate connectivity into tiers - so, for example, a few external aggregation boxes might feed into a larger number of boxes focused strictly on encryption and decryption that, in turn, connect to infrastructure that separates customer connections into multiple ...


2

From a router perspective, what matters are interface. It doesn't change the router behavior if an interface is physical or virtual. You can have either two cables between the router and the switch, each one in its own VLAN, or a single cable configured as a trunk that carry both VLAN Both scenario will works, but they are not strictly equivalent. In the ...


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