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location Boston, MA
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visits member for 5 years, 4 months
seen Oct 11 at 23:32

Feb
22
comment Is there An open source de duplication backup solution?
@user71137 -- the question was how to do opensource backups with deduplication, not how to draw a line with a ruler. Besides, anyone who tells you backups are simple is someone who has never had to do restores.
Feb
16
comment Any thoughts on 6 inch ethernet patch cables?
Did the 6 inch cables hinder or help the jury-rigging? I can imagine situations where using long cables properly routed may allow you to plug certain devices into other devices in the event of a failure, while you wouldn't be able to do that with short cables.
Feb
16
comment Any thoughts on 6 inch ethernet patch cables?
And do you have any photos?
Feb
16
comment Any thoughts on 6 inch ethernet patch cables?
easier said than done -- the patches are often done by helpdesk support people who don't do it often, don't have to maintain it when it gets bad, and frankly don't care. And saying "they should care" is true enough, but hard to actually mandate. And if we made them clean up the mess, they'd make things bad enough that we'd have to fix it anyhow. Kinda like a toddler...
Feb
16
comment Any thoughts on 6 inch ethernet patch cables?
Are there problems with directly connecting devices because there are minimum distance requirements in the ethernet spec?
Feb
16
comment Any thoughts on 6 inch ethernet patch cables?
Have you had any issues with this? Have you run these links at gig? I've noticed that you can't get 6 inch cat6 cables, I assume because there are minimum length requirements for the cat6 spec, but I've got no real evidence one way or the other.
Feb
16
comment What are .nfs* on NFS mounts?
And I believe the NFS server is suppose to figure out when the client closes the file; if the client crashes prior to closing the file, possibly the NFS server won't ever find out that the file is closed, so these files will linger. Go talk to user 19654 (and try to get your UID / username mapping to work consistently across your enterprise) and find out what's up.
Feb
16
comment Cooling requirements for POE switches?
Some vendors don't make the information blindingly easy to find while they always make the power draw obvious.
Feb
16
comment What are .nfs* on NFS mounts?
Unix only reclaims space when the link-count of a file is zero. When a file is opened, unix internally increments the link count. So, if you delete a file while it is open, the file must still exist until that file is closed. This is the NFS server's way of keeping the file around until that client's process closes the file and the server can reclaim the blocks / inodes from that file.
Feb
15
comment Raid 5 with hot spare or RAID 10 with no hot spare?
@zypher: the point is you've only got a limited number of disks in the array, and if you go raid 10 you don't have a hot spare. If you lose one disk, you've got a 33% chance of the next failure destroying 50% your data.
Feb
15
comment Raid 5 with hot spare or RAID 10 with no hot spare?
@chopper: If you lose a disk in R5, then rebuild from spare, then lose another, you now effectively have an intact raid0. That's 3 discrete disk failure events before you lose data. If you have a single simultaneous failure of more than one disk with R5, you're probably hosed (there's the tiny chance you'll lose the hot-spare, in which case you should also buy a lottery ticket...) With R10 and you have a simultaneous failure of 2 disks, you may be hosed.
Feb
15
comment Cooling requirements for POE switches?
Thanks for the link to hard numbers! The difference between the power draw of a POE+ and non-POE device can be 2x or 3x, and that makes a huge difference in the potential cooling required.
Jan
14
comment VMware NAS/iSCSI recommendations - smallish organization
That's the subject of lots of discussion but my experience is that convenience trumps performance, and that you'll have plenty of performance with 10gig ethernet either way.
Sep
3
comment Free alternative to Plesk
@David -- the email issues is definitely a concern, I'm just not sure how much of a concern given that if all my dns is down, I'm not sending outgoing email, relaying email, or accepting email. It would affect outgoing email that's been queued somewhere else and then accepted for delivery after the hypothetical network outtage, but that seems like a rare corner case.
Aug
21
comment Free alternative to Plesk
I've heard this many times, but I have to ask -- if my servers are in a single subnet, and that subnet vanishes from the internet, what's the advantage of having the names of my servers resolve? In other words -- what do I lose by having all my DNS servers running in the same network as my service providing servers? Granted -- I'd rather have redundancy, but if there is none for my servers, why do the DNS records need to be more reliable than the things they point to?
Aug
20
comment How exactly & specifically does layer 3 LACP destination address hashing work?
I think in your case the hash on destination won't get you anything since the switch will see the destination as your server. L2 traffic engineering just isn't very good. And 'hash' in this sort of application is going to be pretty primitive -- figure the best you can do is add up all the bits in whatever address(es) are in use and if the result is 0 go out one link or 1 go out the other.
Aug
18
comment How to reinstall a Server but have a message saying “Our website is currently down?”
So, yes, caching the wrong data may cause problems with weird clients that don't respect TTLs but I think those are getting rarer and rarer because so many things on the internet rely on short TTLs to properly deliver their dynamic (and interesting) content.
Aug
18
comment How to reinstall a Server but have a message saying “Our website is currently down?”
At this point so many things use tiny TTLs that I think it is a solved problem. Services like akamai seem to use a chain of 3 cnames, each with a 20-30 second TTL. www.apple.com, for instance, has the following cname chain: www.apple.com c -> ttl:1600 www.isg-apple.com.akadns.net. c -> ttl:30 www.apple.com.edgekey.net. c -> ttl:4096 e3191.c.akamaiedge.net. a -> ttl30 184.85.29.15
Aug
17
comment Network cables - make them or buy them
Wow. You're totally awesome.
Aug
16
comment Network cables - make them or buy them
You must have an expensive tester to have it test if it is cat3 vs cat5e vs cat6 that quickly. Mine takes almost a minute to run through the tests in cat6 mode.