4,770 reputation
11035
bio website mattdm.org
location Somerville, MA
age
visits member for 3 years, 11 months
seen 22 hours ago

I'm the Fedora Project Leader. I work for Red Hat — and for the Fedora community at large! – but my posts here are all my own.

Previously, I was a sysadmin in the Academic Computing group at Harvard School of Engineering and Applied Sciences, and before that, I made Boston University Linux.


Nov
24
comment How to make ssh match known_hosts to host/ip:port instead of just host/ip?
Clever. Horribly wrong, but clever. :)
Nov
23
comment Is there any browser utility I can use in SSH for Linux
Note that both of these are available in the CentOS base repo, so you just need to yum install them.
Nov
23
comment Fast way to recursively count files in linux
I was just writing almost exactly the same thing, but you beat me to it, with nice examples and everything. :) One minor addition is that if directories need to be differentiated but don't change often, that number can be cached, or if precision isn't necessary, estimated.
Nov
22
comment Comprehensive guide to init.d scripts?
And looks like for RHEL 7 you may have to learn systemd.
Nov
21
comment Images loading speed dependent on server?
Your hosting provider is conflating bandwidth with simple traffic per month. Many providers cap out at some number of gigabyte transferred, either shutting down or charging extra. Yours doesn't have a limit like that. But that's not really bandwidth, of course. Doesn't do much good if it's unlimited 1200bps.
Nov
20
comment cp and cat on Centos 5.5/ext3 is 10x slower for files in certain directories
Cool — glad I could help!
Nov
20
comment How to give an apache user read/write permissions?
Make sure that the directory which can be written to isn't configured to execute php or cgi scripts. Most ideally, make it so it can't even be served out by Apache at all. (If you need to re-display the saved information, use a program to fetch and output it.) This will save you a whole lot of pain later.
Nov
19
comment Linux Routing. Computer A to computer C
Have you considered simply connecting A to C as well? Then each machine has a dedicated gigabit link to each other machine, and you don't have to deal with routing or server B becoming a point of failure for A-C communication.
Nov
19
comment 64-bit and 32-bit Linux distros
See screenshots of it being installed in GUI mode: theosquest.com/2010/10/10/… Maybe you can explain what you're doing in more depth?
Nov
18
comment Repositories for CentOS that don't suck?
I just want to comment that this is by design. CentOS is a rebuild of Red Hat Enterprise Linux, which includes a tailored set of packages which are given careful scrutiny. This set is getting pretty long in the tooth given how ancient (in Internet years) RHEL 5 is. RHEL 6 should address some of that in that it'll have more modern tools included (git, for example). But even then, if you want a wider world, the general answer of "add EPEL" is a good one. Or, if you want the whole universe and are willing to trade off enterprise stability, that's what Fedora is for.
Nov
18
comment Remote Linux server monitoring
Or Icinga icinga.org , which is a fork of Nagios due to that program's problematic open-core development model. It's a lot prettier and is likely to advance in features more quickly.
Nov
18
comment Is SSH Key Exchange more secure than password authentication?
Y'know, part of the sysadmins job is to protect them from themselves. :)
Nov
18
comment Is SSH Key Exchange more secure than password authentication?
Also, as noted in number 2, the users are using the same password everywhere. Sigh.
Nov
18
comment Is SSH Key Exchange more secure than password authentication?
Sirex -- right; they steal your password and use it on other systems. Note in the question that the passwords are used as the "LAN A/D". So, they steal your password from the ssh login server and then have access to the Windows server as well. Additionally, now, whenever the system is compromised, you have to go through the "okay, everyone change your password again" fire-drill.
Nov
18
comment Why does my Apache server keep stopping?
You may see the oom-killer messages simply by typing dmesg. If you're lucky.
Nov
17
comment installing package kernel-2.6.36-2.x86_64 needs 52MB on the / filesystem
More information needed, please. What distribution? Are you using LVM? Do you have other storage available? What all is on / already? (Any other separate partitions?)
Nov
17
comment Man In The Middle Attacks vs. SSL Certificate Authorities
See for example: mozilla.org/projects/security/certs/included
Nov
17
comment Linux: hosts.allow, hosts.deny - how do I allow all except hosts mentioned in hosts.deny
I think this is the best approach. Put ALL:ALL in hosts.deny, and make exceptions in hosts.allow. In this case (allow most everything), that means starting with a really large exception -- but that's okay.
Nov
16
comment Changing memory allocation policy on Linux
Unless you're on Red Hat / Fedora, in which case that won't work. You didn't specify. :) (In fact, on those distributions, the numactl utility, with its man pages, are in the Base group and so installed by default on every system.)
Nov
16
comment Threading of PGP Whole Disk Encryption on server
Beware of the TrueCrypt license. See: lists.freedesktop.org/archives/distributions/2008-October/…