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    Custom rackmount shelf, will this be strong enough?

    Threaded rack stuff is probably just going to be 10/32 threaded. See if you can get some 10/32 bolts, then just have a small piece of wood bolted into the rack. Do that on both sides, then attach a 1x2 or something between them. The idea is just to get a strip of wood bolted on, then you can...
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    Live Broadcasting - Recommendations/help

    You can't just switch HDMI to Firewire. You need an interface that can convert HDMI (which is a video-specific thing) to something the computer can actually work with. There are cards that do this cheaply, but the fact that you have a laptop (which can't take PCI/PCI-E) makes this somewhat...
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    Live Broadcasting - Recommendations/help

    There are devices (baluns) to run Firewire over standard UTP (unshielded twisted pair) cabling - such as Cat6 network cables. It sounds like the repeaters you are using are just like four port hubs which aren't really that stable, especially once you start to daisy-chain them. There are a lot...
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    Large Area Network Design !

    Running any copper cabling between buildings is a terrible idea since you *will* have issues with potential differences - even without considering lighting. Fiber is the preferred option since it is non conductive. Microwave links are an option however the unlicensed spectrums aren't getting...
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    Set up for large conference hall - thinking Ubiquiti?

    schell is dead on about this from a simple RF propagation perspective. The 2.4GHz ISM band was specifically allocated since the water molecule is highly effective at absorbing RF energy at that particular frequency. It's an interesting exercise to be forced to question the typical assumptions...
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    Decrypt router log?

    Type the IP address in the log into a web browser. Should work fine unless a vhost is involved.
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    Network pics thread

    Of course two connectors failed - line and neutral. Kirchoff's current law. Without seeing the inside of the plug, it's pointless to speculate on what the root cause is, because simply looking at the cable eliminates the possibility that it was shoddy assembly that burned it up. Alternatively...
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    A small datacenter build and other projects

    I just punch down the copper uplink ports as the last couple ports on the patch panel. However, I've only had the chance to use cheaper switches that are *exactly* 24 ports. What you could try is mounting a surface mount box inside the rack, then adding four keystone jacks inside there.
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    Popper Pin-outs? Baytech RPC to Digi CM32

    Assuming that it either uses no flow control, or XON/XOFF (software), all you need is: BayTech pin 2 to Digi pin 4 (GND to GND) BayTech pin 4 to Digi pin 3 (Baytech transmit to Digi receive) BayTech pin 5 to Digi pin 6 (Baytech receive from Digi transmit) I don't think the BayTech uses...
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    VGA + Audio over Cat5 problem

    Balun - it's an abbreviation for 'Balanced/unbalanced', which makes sense, since VGA/composite video/consumer audio are all unbalanced, and the transformer adapts them to catX-pair based cables (twisted-pair does balanced transmission *very* well due to the very even common-mode noise coupling)...
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    Custom computer for music production - need help with parts

    If this is a custom build - it's almost certainly going to be windows. I'm a radio engineer myself - which means that I build PC's that do audio playout/recording/encoding 24/7 in mission critical environments. Production has its own can of worms that gets opened, but a lot of this stuff is...
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    Pfsense firewall in Production

    Right - Linux and FreeBSD kernels support SMP. However, that only applies to user-mode programs, like Firefox, Apache Web Server, and MATLAB. Packet routing (and therefore, filtering) are performed in the kernel-space of an operating system. This is the part of a (monolithic) operating system...
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    Pfsense firewall in Production

    It is - and things that run in the userland can take advantage of that. However, pf, ipfw, and other firewall packages run in kernel mode - they have to, since the kernel provides IP routing services. I'm not aware of any general purpose operating systems that support multithreaded kernel-mode...
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    Network pics thread

    The poster specifically stated that the network infrastructure was part of the same plant as the RF equipment. If they are sharing any wiring infrastructure, RF plant grounding practices should be followed. They would be wise to follow Motorola's practices simply because Motorola knows what...
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    Network pics thread

    Actually, no, you are talking out of your ass. First off, the facility is not just a regular datacenter - it's an RF plant which just so happens to carry antennas that have a low-impedance path right into the back of the transmitter - which I'm willing to bet is linked in with those switches...
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    nVidia Professional 3000 vs Intel Desktop NIC?

    Install the Intel NIC in the server - I would recommend PCI-E for a server. Disable the nVidia NIC in the BIOS configuration. Does the motherboard have IPMI?
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    How to Measure SATA power draw

    Measuring current draw - as others have stated - is fairly simple. There are two ways to do this: The first is to measure current directly using the DC Ammeter built into a multimeter. The problem with this is that most handheld ammeters won't do anything above 200mA so that's not going to be...
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    MoCA Cable Plant Back-feeding

    The other thing to consider is that in order for data to pass bidirectionally, a special amplifier has to be used. Now granted, with the ubiquity of cable modems and STB's these days, the majority of amplifiers should have a return path. Alternatively, you could get a directional coupler, which...
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    Patch panel / setup for misc electrical/data lines?

    Get a 1U blank rack panel, and mount some terminal strips to it. Modern industrial deployments use these really small terminal block mounted on DIN rail (very high density). However, that's probably overkill unless you're controlling a chemical process in your basement. I would stick with...
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    How do you deal with multi server environments and custom apps?

    There are cluster filesystems that can be accessed by multiple nodes at the same time. I believe Gluster is one of them. However, a simpler solution would be to use a user management system like Kerberos or LDAP - that way, you would have the same accounts on each system.
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    Blocking ICMP on a Cisco router

    Every ACL ends with an implicit deny any any. I think the poster was confusing this - since the most specific ACL wins, permit ACLs must be entered explicitly to permit traffic. As soon as an access-list is applied to an interface via the access-group command, there is the implicit deny any any...
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    Poll: Who do you trust with your DNS on your home connection? I'm pretty sure that's Level3.
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    USB powered relay and thermal sensors

    Thermistors are best connected using what's called a four-wire configuration. You connect a constant current supply to the thermistor. The current source will push any current required into the sensor. You then connect a voltmeter across the thermistor. The voltmeter has a very high input...
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    USB powered relay and thermal sensors

    GPIO just describes simple digital logic that works at the individual bit level. Hell, if you have a nice hardware parallel port, you have 8 bits in and out right there. Throw a solid state relay off the outputs to switch whatever. It doesn't show up in /proc. To control the outputs, you just...
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    USB powered relay and thermal sensors

    Broadcast Tools has a device which will give you GPIO channels via RS232 (just throw a usb<->rs232 on it). They do 4ch, and 16ch models. They have inputs and outputs. FYI - the relays are just reeds. If you're gonna drive a contactor on an HVAC unit, grab an external relay to control your hvac...
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    Network pics thread

    Whatever training sam-sgc has is completely irrelevant. This is a person who has actual experience on production machines. The idea behind training is to make sure each potential admin/tech/whatever has a certain baseline of fundamental knowledge before they go out and work on actual machines...
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    Network pics thread

    I got the feeling that EMC is the best at taking people to lunch and golfing trips.
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    Running untangle/openVPN setup behind a router?

    Yes, just don't use NAT in untangle. Create a new subnet for your LAN. Create a route to that subnet on the Actiontec, pointing at untangle's outside interface. Create the VPN connection in Untangle (then the entire lan can access the vpn should you choose).
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    best studio monitors speakers (for music playback) around 600$ max

    If you're getting monitors, then most of the small ones are designed for near-field listening (within about 1.5 meters or so from the ears).
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    Network pics thread

    Looks like either the 3000VA or the 2200VA model with an external battery.
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    What's your SSID?

    One does not simply associate with Mordor.
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    Setting up UPS to shut down "servers"

    apcupsd has a windows port, works over the network.
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    Static NAT problems on ASA 8.2

    Working now, thank you!
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    Static NAT problems on ASA 8.2

    I'm trying to have static NAT configured so I can access ssh and http on the server ( via its public IP address (x.y.158.238). For this host, I want to have a static translation, independent of port numbers. The host is running iptables (and it lives in an isolated subnet) so I'm...
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    Static NAT problems on ASA 8.2

    Also, I dont have any issues accessing the Internet from that server, so it's not a general connectivity issue. PAT going outbound is fine.
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    Static NAT problems on ASA 8.2

    Hello all, I am trying to get a static NAT translation working on the ASA 8.2. Here is the actual static command: static (outside,inside) x.y.158.238 netmask tcp 1000 100 the access list allowing traffic to the server: access-list outside_access_in line 2...
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    Forwarding domains

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    Is a 2 mile network realistic?

    The taller the antenna, the better the connection (taller antenna would move the Fresnel zone outside of the ground/tress/crrap).
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    Is a 2 mile network realistic?

    Line of Sight means no trees, buildings, any kind of structure in the way. Any kind of obstruction is very bad for digital RF systems - multipath interference does some very nasty things to connections. Adding more power usually makes the connection worse. Look at the Ubiquity networks...
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    Network pics thread

    Faraday cage only works if it is grounded.