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28

Welcome welcome welcome to the world of the Internet in Australia. Even in our largest population center, we can struggle to get 3Mbps downstream on a business-class ADSL2+ connection. Cable penetration is poor in residential areas, and even worse in commercial so unless you're fortunate you can't get cable internet. And because we're such a sparse ...


13

How about using ovftool to copy the templates directly between hosts? I have used this for VMs before, and it works pretty well. Not sure if that also works for templates, but if not then you can just covert the templates temporarily to VMs for copying them. Instructions, with an example are here. You could also use ovftool to convert your templates to ....


12

For example, Google has over 500 IP address, yet only around 20 data-centers. How can this be. You seem to have a Fundamental Misunderstanding of How The Internet Works. One datacenter houses many servers, and typically has many IP addresses. IP addresses are not like postal addresses - they can move around (through the magic of BGP) From what I have ...


11

After doing some research I believe you are right about sending snapshots. The ZFS SEND and RECEIVE commands can be piped into bzip2 and then that file can be rsync-ed to the other machine. Here are some sources I used: The Oracle Solaris ZFS Administrator Guide page 211 (or web version here) begins talking about about this. I also found a blog post that ...


11

Generally speaking the strategies to connect remote offices (known as Wide Area Networking, or WAN) to a central office break down along the lines of dedicated versus non-dedicated connections. The lines are actually a little blurry because it's unlikely that your company would ever actually run the wires to the remote offices yourselves so, in reality, you'...


11

I wonder how you come to these conclusions about how datacenters operate. Unless it is a very small datacenter, they will have multiple uplinks to two or more NOCs for their AS number(s), and may or may not run their own BGP services. Larger datacenters will typically have multiple redundant links (that is, 4 or more physical connections) to separate ...


8

You very likely have a duplex mismatch on account of the ISP hard-coding their side to 100-Full essentially disabling auto-negotiation on the ISP Ethernet PHY. With the ISP set to 100-Full and your side remaining at auto/auto (a hunch, but a common one), the auto-negotiation on your side will configure the interface to 100-Half -- a duplex mismatch as the ...


8

What do you have handy? If you have any emails from yourself, sent from home, the full headers will contain your IP address (maybe only if sent from a desktop client, not sent by webmail). Can you login to your ISP account page and find it? Do you have any servers you can connect into, and find "last logged in from {home IP}" in a logfile somewhere? Or ...


8

Options: The way I see it, I have three possible approaches, though I dearly hope I'm missing a better one that someone here can point me at. (Ideally one that has me only moving the 40 GiB of actual data, and in a resumable, "background" or speed-throttled method.) Copy the files between datastores through the vSphere client. Advantage: Moving only ~40 ...


7

If you use Linux you can use tc - the traffic control program. It should be standard in your distro. For example, to set the upload maximum speed (in this case 100 kbit per second): $ sudo tc qdisc add dev eth1 root tbf rate 100kbit latency 600ms burst 1540 to set the download maximum speed (in this case 500 kbit per second): $ sudo tc qdisc add dev eth0 ...


7

This can be done, but your users need to either be on differing subnets, or static IPs. This is handled at the Routing Policy level. Create an Address Group for the subnets (or static IPs) you want routed by X2 instead of X1. Then go to the Routing tab. Create a new Routing Policy that states that anything from that one Address Group will egress through ...


7

Yes. It will run over any TCP/IP network. Even the internet. I've seen it operate over 1.5Mb links and for doing basic stuff it's just fine (maintenance, etc). It may however be unreliable or slow, but that entirely depends on the network itself and is not a byproduct of SQL Server. I wouldn't want to run a heavy application over it though.


7

Those four ports on the back of that modem are merely switch ports. You should be just fine adding another "dumb" switch to gain more WAN ports.


6

I'm British rather than American so I'm not aware of the typical expectations from Verizon and Comcast's business internet business, but if the problem is worse at different times of the day I'd suspect contention. Do you have a SLA for the performance of these lines and have you verified that it's being met? That aside you clearly can't expect "near LAN" ...


6

http://communities.vmware.com/blogs/Knorrhane/2008/01/23/how-to-simulate-wan-connections-in-your-own-test-lab-for-free VMware Workstation to simulate the network - $189 Netlimiter 2 Pro to slow down the network - $29.95 Tmurgent to simulate packet loss (and latency) - free!


6

It's rather question of routing. Default route through WiFi, while route with your local LAN mask through Ethernet. Assuming, that WiFi card has IP 12.34.56.78 and Eth card 192.168.1.123 you'd have routing table something like: Network Address Netmask Gateway Address Interface Metric 0.0.0.0 0.0.0.0 12.34.56.1 12....


6

I recommend against doing this in most setups as: every single broadcast packet on that Ethernet segment will be sent to the WAN link. This will cause a lot of unnecessary traffic on the (slower) WAN link and degrade its performance. WAN links are generally point-to-point, whereas Ethernet is a broadcast medium. Not suitable for bridging. There are valid ...


6

If you can transfer a maximum of 6GB per day (assuming zero overhead and zero competing traffic) and you are needing to move "15-60 gigs" at a frequency of "once or twice per week," that works out to 15-120 GB per week, or anywhere from 2-17 GB per day. Because it is necessary to plan for peak demand, and 17 GB is far in excess of even your theoretical ...


6

This article by SciFi author Neal Stephenson is a not-bad introduction. Wikipedia's article on Submarine Cables has a good overview as well. Details of cables differ, but the Wikipedia picture is representative: a bunch of fibers in the middle, a lot of layers wrapped around to protect them and to provide power. The fibers are single-mode (I think - I ...


6

An RODC is still a Domain Controller and requires a full or core installation of Windows Server 2008 or 2008 R2. Since it requires a normal installation of Windows and the installation of the Active Directory binaries, it, by definition, requires a server and not an appliance. It needs to be updated and maintained like any other Domain Controller in your ...


6

With only 17 computers, you really should only be on a single 24 port switch. This is assuming that home run cable pulls aren't out of the question for some reason. You may not be seeing any bottlenecks right now, but are introducing points of failure, and additional overhead when it comes to troubleshooting. You are also giving employees the ability to ...


6

Sure. You need an internal DNS server. If your clients on your network use your internal DNS server (by say, assigning your internal DNS server to clients via their DHCP leases) you can create your own mini-world-wide-web. Create your own TLDs, overwrite other peoples TLDs, go crazy, create records for whatever you want. You could watch the world burn by ...


6

No, carp requires three WAN IPs.


6

You seem to be operating under a number of misconceptions - I STRONGLY URGE YOU to seek professional assistance. Doing what you're asking for in your question is an involved process. For starters, you don't purchase a single "additional public IP address" - IP addresses are allocated in blocks by Regional Internet Registries (RIRs), or through ISPs. ...


5

The native windows tools to do this are xcopy /z and using BITS. Xcopy /z is pretty self explanatory. Bitsadmin is how you manage a bits tranfer in windows 2003, howver if you can install powershell v2 it contains cmdlet modules to do bits transfers. See Transferring (Large) Files Using BITs. My favorite exe tool is XXcopy.


5

The best source, by far, for the future of IPv4, is Geoff Huston's IPv4 Address Report. If you want to follow the news day by day, see the IPv4 depletion site.


5

We've done this before in PFSense. If your IP addresses are grouped together it's easier, otherwise you have to create a rule for each and every IP address. In the WAN Firewall rules, create a rule matching: Protocol: any Source: x.x.x.x (or a range, if appropriate) Destination: any Gateway: (select WAN connection) You might want to create two failover ...


5

A better connection. Point. No client can fix that. We have sometimes 600ms and people complain - line overlaod. Basically, the latency is there. All input is delayed 500ms. A client can not magically handle that. This is like asking "I like driving faster than allowed, what car color will help me not getting tickets".


5

According to Technet http://blogs.technet.com/b/stdqry/archive/2011/12/15/dns-clients-and-timeouts-part-2.aspx later queries are done to multiple DNS servers in parallel. And most people have only one network connection and a fast broadband connection and should normally expect a DNS response within 1s. So I have set my DNSQueryTimeouts to 1 1 1 10 10 0 so ...


5

Looking through google images for datacenter topologies it's easy to see how you might have come to this conclusion. Most of the examples are for small data centers. They have very little in common with topologies in the scale of Google or Microsoft or Yahoo. Here's a good example of an internal view of a datacenter (this is not even close to the scale of a ...



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