BCS's questions

When I run this on an Ubuntu box:

sudo ping google.com -c 25  -l 25

I get about 1 line back every 2 seconds despite the fact that it should (if I'm reading things correctly) send out all 25 packets at the get go. Oddly enough it claims that I'm getting ping times of:

--- google.com ping statistics ---
25 packets transmitted, 24 received, 4% packet loss, time 0ms
rtt min/avg/max/mdev = 23.370/28.067/32.902/2.895 ms, pipe 24

Also, if I want to bail early, I need to punch ctrl-C once for each packet. Does anyone have any clue what could be causing this?

I have a directory A with a large number of sub directories and files and want to get a list of all files named foo that are inside of a directory in A that matches *bar. E.g.:

• Yes: ./goldbar/fiz/baz/foo
• Yes: ./leadbar/foo
• No: ./candy/figbar/foo

I have the some additional constraints:

• I must not descend into directories that don't match the *bar (this is a necessary optimization as it would take to long to scan those)
• I can't allow the shell to do the glob expansion because it returns to many results: (i.e. find *bar -type f -name foo fails)

I think that the -path flag would give me the results I need but I don't know if it fits the first of the above constraints.

Edit: Assume that there are n*10k directories in A that match *bar. i.e. anything that tries to build a command with all of them (as opposed to handling each one in tern) will fail.

This question (and some more research) has revealed that OpenVPN isn't for me. So, what are my other options? In particular things I need/want (most important first) are:

1. A server daemon that runs on Linux without kernel modules
2. Clients work from behind NATs and Firewalls.
3. Free/FOSS
4. Support for PPTP, L2TP or L2TP/IPSec PSK/CRT
5. A architecture that makes all accesses equal: if the server is to have access to the VPN, then it must be a client. Just like everyone else.
6. Minimal configuration/state.

The first 3 are must haves and the last is a nice to have. The rest I could live without, but then again I could also live with nothing.

I'm looking to set up a VPN (OpenVPN is my first choice but I'm not stuck with it) in such a way that the server that hosts the VPN is not visible from within the VPN. That is; any packet that a client sends via the VPN interface will get delivered to another client's VPN interface or get dropped. In the other direction, the server shouldn't have a VPN interface at all and normal network operations shouldn't be able to send packets on the network.

Can this be done?

All the docs I have found have assumed that clients will connect via DHCP (this requiring that the server connect at least to that extent) but I can't think of any reason that a VPN couldn't use static IP's or that the DHCP server couldn't be implemented inside the VPN (see edit) server without setting up a VPN interface on the server.

Edit: Based on the link on bridged mode from Phil Hollenback's answer it seems that OpenVPN does in fact have the "internal DHCP server" that I'm thinking of.

I'm looking to set up a VPN server and I'm trying to figure out what software to use. My problem is that I have no idea what the term for the arrangement I want is so I can't really google for it. What I want is to have a "virtual" LAN where the only access is by VPN, where having access to the VPN only give you access to other VPN clients; not to the general internet, and not to the server running the VPN.

My primary use case is getting uniform access between clients I own where one or both may be behind a NAT and/or firewall that may not have a consistent IP.

(p.s. Given my budget I'll have to stick with freeware/FOSS.)

Edit: The VPN server is not in the same NAT/Firewall/IP situation. It's able to serve up whatever I want from a static IP.

I've got a copy of the Pulling Strings with Puppet book (written in 2007) but given that it has a bunch of equivocal language, I'm wonder how much has changed since then? I've found this Release Notes page and a (short) summery table at the top of the language tutorial but neither have dates, so I don't know where to start (and the more detailed notes make for rather dry reading).

Does anyone know of a page that list thing that have changed since that book was published?

I'm looking for a truly minimal usable linux install: the only requirement for the install is that it be able to install a .deb file (that has no dependencies) from the local file-system. (I'm assuming that if I can do that, I can then use that to bootstrap to whatever I actually need).

An ideal distor for my needs would consists of a kernel and an initramfs with nothing but dpks and init. In reality, I expect I will have to settle for something between that and DSL.

Edit: I'm not looking for an installer per se, but rather something that could be booted via an ISO or via PXE. It doesn't even need to leave the system in a re-bootable state.

As Linker3000 pointed out, what I'm looking for may be closer to a embedded distro than anything else.

Is there a way to install mysqld via apt-get and have it a non default path for the data files?

I know I can install it with the defaults and then move stuff (I've done that) but then I have about a dozen different places I need to update things (4-5 in my.cnf, 6-8 for app-armor, and I think there was somethings else that I'm forgetting).

Edit: I'm assuming/hoping that the relevant config files are all generated at install time rather than being hard coded as static content. Assuming that, what I need is a way to have apt-get pass on the flags to adjust the variables used to specify the relevant paths.

A few days ago I installed mysql-server on a machine and then discovered that it was putting it's data file on a partition without nearly enough room. So (because there was nothing I cared about in the DB) I shut it down, sym-linked /var/lib/mysql to a blank directory on another partition and tried to start it back up.

In short; MySQL now won't start. Upstart seems to think it's running (that is if start mysql doesn't hang) but there is no mysqld process. I've tried re installing (apt-get purge mysql-server; apt-get insatll mysql-server) but it seems to be keeping something around (for one thing, it's not asking me to set the root password like it did the first time) and it still wont start.

How do I do a clean reinstall that completely ignores anything that the last install did?

Oh, and is there a way to tweak the config files before apt-get starts up mysqld?

I regularly get ping times (to google.com) on my netbook over wireless (802.11) of:

1. 500-4500ms for about half the time
2. 100-150ms for the rest of the time.

It seems to switch back and forth on the order of minutes.

Regression:

It doesn't seem to correlate with anything I can see:

• location (I've seen this when using at least three different networks in two different states),
• proximity to the AP,
• other people moving around.

It's been that way almost from the get go. If it weren't for the fact that it does get good performance some of the time I'd write it off as bad antenna design. Any ideas?

p.s. How long can ping times get? I've seen 3-5 sec here and once witnessed (as a result of a borked router config) >90 sec.

I'm thinking of a situation where I would have something that creates a copy of a directory, tweaks a few files, and then does some processing on the result. This wold be done fairly often, maybe a few dozen times a day. (The exact use case is testing patch submissions; dupe the code, patch it, build/test/report/etc.)

What I'm looking for could be done by creating a new directory structure and populating it with hard links from the origonal. However this only works if all the tools you use delete and recreate files rather than edit them in place.

Is there a way to have the file system do copy-on-write for a file?

Note: I'm aware that many FSs use COW at a block level (all updates are done via writes to new blocks) but this is not what I want.

I've installed a bunch of cat-5 and when I check it for continuity and polarity it seems fine, but when I hook up a pair of laptops with a x-over cord and try to ping between them, they can detect there is something on the other end but I get 100% ping failure (mixed between "hardware failures" and "timeouts"). I punched a few jacks on the end of a length of cable and that works just fine, so I know I can make good connections.

Any idea what might be causing it?

My current best guess is that it has something to do with my the wires being bundled together. How tight can you bundle cat-5 without causing problems?

What it turned out to be:

In short: bad test equipment.

The long version: I borrowed some a better tester and it said that all of the cable was good but I still couldn't get data through it. So I yanked the shortest segment out of the wall (man I love nice spacious attics), re-terminated it and brought it to a guy with a better cable tester and even it said I was doing things right (or at least I was enough of the time that I shouldn't be seeing the failure rate I was). Then I tested the patch cords I was using to do the test... Bingo! They were bad. After getting a known good replacement (and disposing of the old one with extreme prejudice) everything works.

I still don't know why the patch cords consistently worked on a few ports and none of the others but I now have tested everything in the wall and it all works!

I'm looking for an app that I can run to test available bandwidth (and error rate) over a LAN. I'm thinking of a pair of programs that run on two computers and send a big known block of data from one computer to another and checks it on the receiving end.

If I were on Linux, I could get somthing working with time, cat, nc and md5 or diff but I'm on Windows.

Does anyone known of a source for open back, low voltage, old work, electrical boxes that are intended to be installed through the Sheetrock and mount to studs?

I've found boxes for old construction like this that mount on the Sheetrock and for new construction like this and this that mount to the studs.

What I have is an existing building where I need to install Ethernet cable inside the walls without ripping out all the Sheetrock. I'm not to thrilled with the Sheetrock mounted boxes and know that with some effort a box can be mounted on the studs (I've seen it done).

Does anyone have a link for recommended network wiring for office space? Runs per wall plate, wall plates per room, that sort of thing.

I have a USB device (USB to RS-232) that works on some computers without drivers but not on others. This is a problem because I don't have the drivers disk for it nor any info on who made it.

Are there any tools that will tell me what kind of device it is or whatever info windows (and other OS's) pulls in when it's trying to set it up?

My company is building a system that will need to use user authentication and web services (WCF or ASMX whichever works, the differences are all confined to a tiny slice of code anyway) and our current hosting provider is somewhat "flaky". They are a low cost provided that seems to do Windows hosting as a second line service and explicitly doesn't support WCF and I've never gotten ASMX working exactly right.

Does anyone have experience with any reasonably priced web hosts that support WCF (or even ASMX)? I'm particularly interested in the setup and configuration being nice, direct and using well known system.

I have a XP pro, SP2 system that is offline (as in TCP over sneakernet) and essentially un-patched. The printer (HP LaserJet 5p) works fine sometimes but as soon as anything goes "wrong", like I get more than one item in the print queue, I (often as not) end up having to manually clean the print queue and reboot.

The general mode of failure is that once things go bad the printer seems to lock up. The computer seems to be fine but trying to delete a print job just doesn't work, the job never disappears. Some times I can get result by power cycling the printer, restarting the spooler and manually clearing the print queue directory. Sometime it seems to be in an invalid state where the printer spews over-sized text or gibberish.

Because I'm offline, I can't simply run Windows update and so are there any specific updates out that address issue in the print spooler service that might help?

(If you can remember an update it's a good bet it's not on this computer)

<soapbox>

Why is it that anything involving visual output drivers under windows sucks? Video drives crash more systems thatn anything else I've seen and printers never seem to work correctly.

Oh and any software I've used from HP sucked, even the drivers on there current offerings. (400MB for a minimum install!? No option to not install there image editing program that I'll never even touch!?)

</soapbox>

What should I be aware of when bringing a computer on an airplane?

general answers welcome but...

I'm particularly interested in:

• Are computers bothered by X-ray machines or anything else that carry-on or checked baggage is exposed to?
• What kind of red flags would packing a non laptop raise with the TSA?
• Are there any setups known to work well for packing around larger system (like server scale)?
• Has anyone seen one of those cases bands use to pack there sound equipment used to mount a server?

(In case you didn't spot it, I'm puzzling out what it would take to build a mobile server farm for fast, short notice deployment. FWIW it's more likely to end up in a story than on a plane)