Quick [tech] Questions Thread

[Venkman]

Ah good point about Linksys. Yea I had a Belkin router once. Once. /dannyvermin.

A couple of folks I know love their Airports. Nothing against the device per se, but too expensive for what I need.

I'll look up the security things about Asus. I'm liking that model more and more. I don't live in a densely populated city or anything, but I also don't want a device/platform so insecure even some local yokel could screw with it.

Edit: meant to ask: was the Asus (and apparently Linksys) issue one of those where people weren't changing the default settings on their browsers? Some of the quick googl'ing I did implied that, but did also talk about how Asus updated their firmware and Linksys was "aware of the issue".

Exploiting default settings is one thing. I put that somewhat on the end user. But if it's more than that, I'd be worried.

[Chimpy]

The ASUS one was that if you used the USB port to attach storage, people could acess the file system of the attached device from outside of the local network. I don't think this was isolated to those who did not change their default username/password.

I can't remember where I read the article, it was a couple months ago though.

[Venkman]

Yea there were a few Feb and early March articles I found. Some were pretty egregious. This article for example went through a bunch of notes. Interestingly, in the comments, two themes seem to come up:

• There are fans of Buffalo routers; and in large part because:
  
• There are fans of the DD-WRT firmware which come by default on Buffalo (guess can be side-loaded on others)?

[Chimpy]

Buffalo hardware is absolute shit. We used them running DD-WRT as cheap access points for a dumb "per unit wireless" setup for apartment complexes at the ISP I worked at and they were horrid. Of course, this was a few years ago but I still would never buy something with their name on it. Also, Buffalo does not install DD-WRT by default, they install their own custom firmware which is based on DD-WRT. Most of those people who are fans of it because it "has DD-WRT" are people who hear all the "DD-WRT > all, if you don't use DD-WRT you are a n00b" comments on the internet and jump on them to be in the cool kids club.

If you are wanting to go DD-WRT/Tomato/OpenWRT, just buy hardware that you see is supported by the newest release of said OS build and buy that and flash it yourself.

[Trippy]

ASUS RT-AC66U Dual-Band Wireless-AC1750 Gigabit Router- $200 avg ($168 on deal) Good price, Gigabit WAN which is nice but I'll never get that from Cox. Not sure if those antennae are just something they threw in for looks or if they really do anything.

I have the NetGear Nighthawk which is a direct competitor to the above router as both have "AC1900" support. My previous long-term router was the previous gen Time Capsule which worked very well. The internal power supply on that died though after many years so I switched to the latest gen Time Capsule. Unfortunately the one I got couldn't keep a stable connection so I replaced it with the Nighthawk. The USB attached storage (aka "ReadyShare") didn't work so well for me on the Nighthawk so I turned it off. The wireless connection part is working fine.

[Venkman]

Nice. Thanks guys. Good points on Buffalo Chimpy. I had never even heard of DD-WRT. I'll check out that router Trippy.

[Lantyssa]

I have a NetGear N600 and it's served me well.  I don't have that many users at once, though I do have a few switches hanging off it since we have computers, consoles, printer, and NAS plus any visiting devices.

The older NetGear that got hit by lightning was solid.  D-Link isn't too bad, but is definitely built more cheaply.  I think I'd pick Netgear between the three, with a Linksys being at the bottom of my list.

[Hoax]

I'm not sure I'll ever forgive Netgear for those flat silver routers they were making way back in 2002-6 that were such utter utter shit. They were also way ahead of the curve in terms of the end of useful customer service. I remember calling them, getting India then being told "if you want real CS you need to pay a membership fee". Fuck those guys.

[Morat20]

Does anyone have any idea why, when I'm forced to reboot my router and internet connection, it takes Windows 7 approximately eight million hours to see the wireless connection again?

Last time every other wireless device in the house -- iPads, phones, Xbox, laptops -- saw the network the second it came up. It took Windows 7 a good ten minutes, despite me hammering the refresh button.

It simply refused to admit that wireless connection even existed. It wasn't an option to try to connect to.

[Salamok]

Gigabit on your 4-5 port router isn't exactly a premium item, I would go so far as to think that anything that didn't have gigabit is using outdated crap you don't want.  I have a netgear wndr3800 I thought I was happy with but here I am at the year mark and it is displaying typical wireless router meltdown syndrome.  I think my next router is going to be an airport extreme and if that one starts crapping out before the 2 year mark I'm going to build my own damn wifi router.

[Numtini]

The USB attached storage (aka "ReadyShare") didn't work so well for me on the Nighthawk so I turned it off. The wireless connection part is working fine.

We have an earlier model and I'd say the same thing. For storage, it just wasn't reliable. The throughput on the router is great and the range is decent though.

[Yegolev]

I'll risk being completely unhelpful and say that my WRT54GL router is still humming.

[Salamok]

I'll risk being completely unhelpful and say that my WRT54GL router is still humming.

And since Linksys is in touch with the world they think you will upgrade to this:
http://www.cnet.com/products/linksys-wrt1900ac-wireless-router/

They probably can't give you the same 10 years of trouble free performance but hey it is really all about the crappy blue retro looking case.

[Stormwaltz]

Trippy and Chimpy - there's a good chance you were right.

I got the PC working again and tonight I heard some weird noises from inside the case. I cracked it open and investigated. When I powered it up I found the PSU exhaust fan has stopped working.

My first priority has become to replace that. We'll see how performance is afterwards. It's probably still a good idea to upgrade the 2009-vintage mobo, CPU, and RAM.

[Salamok]

So I was building a server using Dell's server configuration tool and I was curious what would be a faster RAID setup:

8 drives in RAID 5 using: 300GB 15K RPM SAS 6Gbps 2.5in Hot-plug Hard Drive

OR

3 drives in RAID 5 using: 1.2TB 10K RPM SAS 6Gbps 2.5in Hot-plug Hard Drive

On the one hand you have spindle speed and more drives to stripe and on the other your presumably have a much greater storage density.  Is this a no brainer shoot from the hip decision or is it impossible to answer without more detailed performance statistics for each drive?

The chasis can handle 24 drives so leaving room to upgrade the amount of storage I have doesn't really impact my decision overly much.

[Trippy]

Faster for what? Reading or writing or both?

Is this software RAID 5 or are you using hardware RAID cards?

[Salamok]

Hardware raid and although I realize RAID 5 is more conducive to faster read speeds I would think faster drives would increase both read and write speeds.

edit - the setup I am looking at is building a big monster hyper V host system to run our core business application, I was planning on a RAID 1 channel for the primary and log drives (so host os + 3 vxhd's for the 3 guest VM OS drives and 3 more vxhd's for the guest VM logging drives) then throw all the data drives for these on a RAID 5 channel (a vxhd for the sql server databases, a vxhd for the oracle database, a vxhd for the IIS websites).  Works out to each of the 3 VMs having 3 vxhd's mounted (os, log and data).

edit2 - According to Tom's Hardware the gains when using 8 drives vs. 3 drives can be dramatic and I think I can count on Dell to not sell me 300gb 15k drives that perform significantly worse than 1.2tb 10k drives and most likely even perform better.  So I guess it is pretty safe to assume that the 8x15k/300gb drive RAID 5 setup will perform better than the 3x10k/1.2tb drive setup.

[Yegolev]

I leave that sort of thing to the SAN engineers, but just looking at it real quick my gut tells me 8 drives will be better than 3, provided your striping works worth a damn.  Because once you have to read from disk, you have already lost.

[Chimpy]

Your definition of "monster" Hyper-V box and mine must be in totally different universes. I am curious as to why you are virtualizing if you are putting everything on one host (including storage) if this is for a single application.

As far as performance goes, the general consensus is that RAID 5 with disks 1TB and larger is bad juju and you want to go with RAID 6 with larger disks as your chance of disk failure is highest during a rebuild. Which means you need to have more disks than just the 3 you are speccing.

Which model Dell are you looking at? You can get 15k drives in 600GB if you go with 3.5" instead of 2.5".

If all 3 VMs require even a decent amount of IOPS you are going to have performance issues running them on the same LUN.

I highly recommend going with a SAN of some sort (and since you are talking Hyper-V, using a Cluster Shared Volume to store your vhd files on even if your cluster only has one host to start, that way you can add hosts and migrate guests between them with a lot less hassle). The MD3220i is a decent enough SAN (though it does not have a hardware VSS provider so if you use something like Veeam for backup you can't do off-host backup processing, which is lame.) The base model EqualLogic might fit the bill for you.

What kind of specs are you looking at? Also, if you are currently running on Dell hardware, they have a nice tool that you can run for like 24-48 hours which you send the data to them and they analyze it and tell you what your target IOPS are for the application.

[Salamok]

A decent SAN is going to be over budget, current trend in my sector seems to be moving away from SANs for apps with smaller volumes of data.  The app is a piece of crap "enterprise" java web app with an oracle database (soon to be migrated to MS SQL Server), we also have a light duty SQL Server that stores supplemental data to the enterprise app mostly custom stuff we wrote that integrates.  I wouldn't consider any of this large scale and any performance problems we currently have are pretty likely due to the poor quality of the enterprise app.  I was hoping to pick up some gain by setting up a virtual switch in hyper V and having the application VM and database VMs talk over that.

[Chimpy]

Are you running separate servers for your databases or running them as separate databases inside the same instance of Oracle/SQL? It sounds like you are running the former if you are talking about using an internal to the host network connection.

If you are transferring that much data between databases/apps that you think network latency and throughput are going to give you big performance gains you are not going to want that data coming from the same LUN, regardless of the speed of the disks in the host.

Also, RAID 10 is how you probably want to be configuring your disk as that is the best performance for transactional stuff. You could try it all running off of one RAID 10 pool.

[Lantyssa]

Disks are cheap, so I like RAID 10.

[Venkman]

Still haven't settled on a router. However, question about a family member's network.

They've got a Verizon DSL modem/router. It's 4 ethernet ports with built in wifi, in an office where they have six devices that need wires. They've been swapping ethernet cables in and out for devices as needed. I didn't know this until a few hours ago. It rankles.

I don't like modem/router combos but I don't know if they have a choice. How hard would it be to plug in an 8-port ethernet router into their modem/router, so they can get all the ports they need and then some? Is there any setting change I need to make in the DSL modem/router to let the router (which I'd plug into port 1) be able to sub-divide IPs further? Is that how it even works? I've never done anything more than worry about one router at a time.

If there's a For Dummies site out there for something like this, I'd be happy to read it.

[Trippy]

I don't like modem/router combos but I don't know if they have a choice. How hard would it be to plug in an 8-port ethernet router into their modem/router, so they can get all the ports they need and then some?

Have them get an 8-port Gigabit switch like this one. Then they just connect the two with a regular Ethernet cable and it just works*.

Is there any setting change I need to make in the DSL modem/router to let the router (which I'd plug into port 1) be able to sub-divide IPs further?

No.

* Technically you have to plug the Ethernet cable going from any of the ports on the router to the "uplink" port on the Ethernet switch. These days, however, any of the ports on even the cheapest Ethernet switches are "Auto-MDIX" which means any of them can act as the uplink port. If they happen to somehow get an ancient hub/switch that has a port specially marked as "Uplink" on the unit they should use that port instead.

[Venkman]

That's perfect, thanks Trippy!

[Lantyssa]

Yep, it'll work fine.  I have a router off my DSL, and then a switch connected to that for all the TV components.  At the old house it was reversed since the computer room was upstairs and the TV by the cable modem.  Never had an issue except it is an old switch that has a few bad ports.

[Rendakor]

My font for Wikipedia recently started looking weird; I can't think of anything I did to change it, and it only happens in Firefox (v26). Things look fine in Chrome. Anyone have any ideas?
Pic:

[Viin]

Is it zoomed out maybe?

[Trippy]

My font for Wikipedia recently started looking weird; I can't think of anything I did to change it, and it only happens in Firefox (v26). Things look fine in Chrome. Anyone have any ideas?
Pic:

Yes they changed the CSS:

http://en.wikipedia.org/wiki/Wikipedia:Wikipedia_Signpost/2014-03-26/Op-ed

which may be affecting Firefox. Try clearing your browser cache.

[Rendakor]

My font for Wikipedia recently started looking weird; I can't think of anything I did to change it, and it only happens in Firefox (v26). Things look fine in Chrome. Anyone have any ideas?
Pic:

Yes they changed the CSS:

http://en.wikipedia.org/wiki/Wikipedia:Wikipedia_Signpost/2014-03-26/Op-ed

which may be affecting Firefox. Try clearing your browser cache.

No luck.

[Viin]

Try upgrading to 29? (or 28 if you don't want beta I think).

[Rendakor]

Went to 28, still nothing. I guess I can start using Chrome for Wikipedia in addition to YT uploads.

[apocrypha]

There's an addon called Theme Font & Size Changer that I use on the living room PC to make webpages more readable on a high DPI screen. Might be worth a try.

[Miasma]

The first comment on that page explains an opt out but it looks like you would have to be logged in.

[Rendakor]

Except I'm not trying to opt out of the intended changes; my text doesn't look like it does in their example picture.
On the right is what it's supposed to look like, on the left is what it looks like on my end. I also don't even have a wikipedia account, nor do I feel like making one on the hope that it fixes.

apocrypha, might try that out, thanks.