1,407 reputation
1711
bio website redhardsupra.blogspot.com
location Laurel, MD
age 37
visits member for 5 years, 5 months
seen 19 hours ago

Mar
30
comment tcpdump How do I use it to capture all traffic headers
if you're actually utilizing full 100MBit/sec (or do you really mean 100MByte/sec?), the first thing to look at is the drive you're dumping it to. I often do dumps directly to an external drive, and then I keep bumping into USB bandwidth limits (22-30mbyte/sec), so I started using eSATA and that aliviated that problem, but it's still not completely eliminated. If you have loads of traffic, you might need to build a RAID (not RAID5, that's really slow for writes!) to support full speed captures. The reason why payload scrubbing would be nice is it would minimize the write throughput.
Mar
30
comment tcpdump How do I use it to capture all traffic headers
#4 is really hard to do. You never know how many more packet types are encapsulated in the packet. But before you do that you must do TCP and IP reassembly. Libnids is the only library I found that does IP defragmenation and TCP stream reassembly. So first you'd have to recreate all the streams separately, then detect how many encapsulation levels there are, then decide which of them you dont need, and filter these out.
Mar
30
comment Good filesystem for 20TB hardware-controlled RAID5 array?
If the size limit stems from block size and number of blocks, why not up the size of blocks? Unless your data set largely consists of <4k files, this should not be a problem.
Mar
22
answered Compare two user lists in bash
Mar
16
comment Mac's Apache virtual hosts playing up
Do you have NameVirtualHost *:80 somewhere in your config?
Mar
12
answered What's the difference between socat and netcat?
Mar
9
comment wa (Waiting for I/O) from top command is big
THIS document is fantastic in explaining spotting bottlenecks using the tools mentioned above. Officially it's about NIC tuning, but the techniques and tools presented really have a much broader application than just that.
Mar
4
comment Secure LAMP server for production use
Apache Hardening on a sister site.
Mar
4
comment What are the mandatory Linux kernel modules to run inside of ESXi
@Zoredache got it exactly right. I want a cruft-free, lean mean syscall machine ;)
Mar
4
asked What are the mandatory Linux kernel modules to run inside of ESXi
Mar
4
answered How to Minimize Linux Server Reboots
Mar
2
answered Best practice, or generally best way to set up web-hosting server, permissions, etc
Feb
28
comment Can ESXi pass video card to VM to do CUDA?
I configured the video cards to do passthrough, however I still do not see them inside of the VM, or cannot add them to the VM in VM guest settings as a video card or as a PCI device (they're grayed out). Are there any other tricks I should be aware of?
Feb
28
comment HTTP response time profiling
Upvote for statistics inside of awk ;)
Feb
25
comment Can ESXi pass video card to VM to do CUDA?
BIOS is updated, all the VT-x/VT-d are enabled. How do you pass-through a video card in ESXi? I thought that's what vmware-tools do.
Feb
25
awarded  Student
Feb
25
asked Can ESXi pass video card to VM to do CUDA?
Feb
23
comment *nix OS that is easy to update to latest software
There's servers and then there's servers. Are you running a hospital on it, or your own web/mail? I have a file server on arch with 230+ days of uptime on a 7yr old computer, so it's obviously stable, as long as hardware underneath it is healthy.
Feb
23
answered *nix OS that is easy to update to latest software
Feb
20
comment Can enabling a RAID controller's writeback cache harm overall performance?
Would you mind putting together your data in some sort of structured table? This is some very interesting observations you're making, I'd like to see if there's a pattern.