6,954 reputation
21738
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location Boston, MA
age
visits member for 5 years, 5 months
seen Nov 11 at 7:54

May
8
comment Domain reg - own server - need nameserver
I'm a control freak. I don't do anything important on that box. I did/do it to learn exactly how things work. I would never suggest you do this for anything even slightly important, but it is valuable / useful to know how the whole stack works. Oh -- and the VPS service I have is extremely inexpensive.
Apr
27
comment Setting nagios location in map
@mech: The whole point of the parent mechanism is to allow nagios to tell the difference between a host being down and a host being un-reachable because the network between nagios and the monitored system is down. So in a nagios world, ideally, you put the gatways on nagios and make those the parents of the other things.
Apr
20
comment What are useful .screenrc settings?
@murail I prefer using the scrolly wheel thingy in my mouse when I'm using putty; just habit. @mikeage -- I found that if you get rid of the seconds on the clock it makes the scrollback buffer on screen work pretty well. Of course, I mostly have a clock on my screen to avoid the stupid idle timeouts we've got on our damned firewalls. grrr.
Feb
27
comment Network Sniffing and Hubs
It looks like there are some old netgear products sold in the amazon marketplace, but their "marketplace" is pretty similar to ebay. Netgear doesn't appear to be making these things any longer. And geez, $80? For a hub? Really? I'd think cgi.ebay.com/290430680833 is a far better deal...
Feb
27
comment Network Sniffing and Hubs
These days the only reliable place to get a hub is your basement. Otherwise, look on ebay, but once there you may as well look for old nortel switches or similar less desired but still really nice networking equipment. Old nortel switches, for instance, can mirror to a port based on things like the source or target MAC address as well as source port or vlan.
Feb
27
comment Network Sniffing and Hubs
@eater - that was certainly the case long ago when these things came out, but I'm not sure it's still the case. I'd expect that the chipsets to make 10/100 hubs are probably no cheaper than a switch-on-a-chip chipsets, and maybe more expensive because they aren't made in volume anymore. Certainly any old-stock is exempt from this, but stuff on newegg? I'm not sure you'd win that bet often enough to want to play the game.
Feb
25
comment How do I clear the “s” permission on a directory in Linux?
In unix, the inode is the thing that gets the permissions.
Feb
24
comment ZFS Like Alternatives on Windows
Snapshots, volume sizing, and cloning aren't functions of a SAN, per se. They may be features of a specific implementation of a SAN, but in general with a SAN you just get a reliable way of storing blocks on a random access device. And, it is far easier to implement this functionality using a NAS than a SAN because the NAS operates at a filesystem layer instead of a block-level storage layer.
Feb
24
comment Why are datacenters built over a wide area instead of using taller buildings?
Right -- one summer is actually the smallest of these facilities. The 111 eighth ave facility is a city block that was originally a warehouse / repair facility for New York city's MTA. Not a small building, but not a purpose-built datacenter.
Feb
24
comment Why are datacenters built over a wide area instead of using taller buildings?
In cities typically old cement warehouses are retrofitted to be datacenters. This is especially true of "cold storage" facilities that were originally designed to keep stuff cold. Nice hefty cement floors that can support huge weights, no windows, fireproof construction, and heck, they're already there so no permits to pull or neighbors to annoy with construction.
Feb
24
comment Why are datacenters built over a wide area instead of using taller buildings?
Warehouses in cities tend to be multi-story affairs. Lots of 10 story cement buildings around where I live, typically painted white with "cold storage" written in block letters on the side...
Feb
22
comment How can I set up VLANs in a way that won't put me at risk for VLAN hopping?
The basic problem is that there are also VMs in the mix and he must trust that the VMs are as trustworthy as the switches.
Feb
22
comment What else do I get with Cat 6 beyond future proofing my wiring?
If it isn't cat6a you've got no promises from anyone. This includes cat6 or cat5e or even cat5. A single run is far more likely to work properly than 50 cables in a conduit all running 10gigE because of alien crosstalk issues. But in practice, cat5e usually works. The question here, of cat5e vs cat6, though, is simple -- no value in 6 vs 5e at all. Zero. Zip. Nada. Zilch. Just more money for the cable guys.
Feb
22
comment What else do I get with Cat 6 beyond future proofing my wiring?
None of those features actually make anything work faster. Just like plumbing -- if your pipes are plastic or copper or gold, or steel, they all flow the same volume of water for the same inner diameter pipe. Sure, some of them have higher melting points or corrode faster, but that's not relevant to the question at hand.
Feb
22
comment What else do I get with Cat 6 beyond future proofing my wiring?
But I was lucky. Some of the luck was that I was careful in crimping the ends (a cable tester actually said the cable tested as cat6) and I was lucky that the alien crosstalk around the cable wasn't enough to cause errors.
Feb
22
comment What else do I get with Cat 6 beyond future proofing my wiring?
When you're working with networking cables, it either works or it doesn't. If it doesn't, it either doesn't work at all or it works poorly and you get errors, and if you get errors, the throughput falls so far through the floor that it is nearly unusable. So a bad cable that links up will be 1/100th as fast as the rated speed if you put lots of data through it. tl;dr --> as fast as if I had used fiber.
Feb
22
comment What else do I get with Cat 6 beyond future proofing my wiring?
Plug it into the switch and the network port on the device.
Feb
22
comment What else do I get with Cat 6 beyond future proofing my wiring?
Not to mention that there is no advantage of cat6 over cat5e. You need cat6a cables to safely run 10gig.
Feb
22
comment SATA SSD in Dell Server
I thought that dell has changed the firmware of their raid devices to only allow dell branded / approved devices in their arrays?
Feb
22
comment replacing an ethernet backbone with fibre optic
@Mark: gig ethernet works just fine on cat5. Read the spec. en.wikipedia.org/wiki/Gigabit_Ethernet#1000BASE-T