Episode 136 – All in the Details
Podcast: Play in new window
Subscribe: Apple Podcasts | Android | RSS
Downloads:
MP3 format (for Freedom Haters!)
OGG format (for Freedom Lovers!)
Total Running Time:
Un-edited Live session – http://www.youtube.com/watch?v=don10ODMb9A
Contact Us:
show (at) smlr.us or the Contact us page
Summary
Kernel News: Mat
Time: 8:35
Distro Talk: Tony
Time: 10:30
Tech News:
Time: 39:55
Toolbox
Time: 58:20
Conference Scene
Time: 1:04:45
Security Bit
Time: 1:11:00
Is it Alive? – Mary
Time: 1:22:45
Listener Feedback
Time: 1:27:35
Outtro Music
Time: 1:37:10
Intro:
Tony Bemus, Mat Enders, and Mary Tomich
Sound bites by Mike Tanner
Kernel News: Mat
Time: 8:35
mainline: 3.17-rc7 2014-09-28 stable: 3.16.3 2014-09-17 longterm: 3.14.19 2014-09-17 longterm: 3.12.29 2014-09-30 longterm: 3.10.55 2014-09-17 longterm: 3.4.104 2014-09-25 longterm: 3.2.63 2014-09-13 longterm: 2.6.32.63 2014-06-18 linux-next: next-20141003 2014-10-03
Distro Talk: Tony
Time: 10:30
- 9-22 – Salix 14.1 “Fluxbox”
- 9-23 – Linux From Scratch 7.6
- 9-26 – SparkyLinux 3.5 “MATE”, “Xfce”, “Openbox”, “JWM”
- 9-26 – Oracle Linux 5.11
- 9-26 – MidnightBSD 0.5
- 9-26 – OpenMandriva Lx 2014.1
- 9-27 – OpenELEC 4.2
- 9-27 – Netrunner 2014.09.1 “Rolling”
- 9-27 – Qubes OS 2
- 9-30 – CentOS 5.11
- 10-1 – Chakra GNU/Linux 2014.09
- 10-1 – KNOPPIX 7.4.2
- 10-3 – GhostBSD 4.0
Distro of the Week: Tony
- Fedora – 1403
- CentOS – 1816
- Debian – 1940
- Ubuntu – 2004
- Mint – 2286
Tech News:
Time: 39:55
Why Google is pushing Android One at the expense of open source
http://www.itworld.com/mobile-wireless/439793/why-google-pushing-android-one-expense-open-source
The Toolbox
Time: 58:20
Nicstat
Nicstat is a Solaris and Linux command-line tool. It prints network stats for all of the network interfaces on a machine. This includes packets, kilobytes per second, average packet sizes, along with much more. The developers are former Sun Microsystems employees, Tim Cook and Brendan Gregg.
As Tim Cook calls it on his blog the “Network Monitoring Tool You Did Not Know You Needed .”
The nicstat utility is to network interfaces what “prstat” is to processes, and “iostat” is to disks. When you first start nicstat, the stats for the time from system boot until the present are displayed. Let’s look at the command and some output:
If you just run nick stat this is what you will get:
$ nicstat
Time Int rKB/s wKB/s rPk/s wPk/s rAvs wAvs %Util Sat
05:47:01 p6p1 27.42 1.76 23.24 16.40 1208.0 110.0 0.24 0.00
05:47:01 lo 0.00 0.00 0.00 0.00 140.3 140.3 0.00 0.00
These are what those headings mean:
-
Time – The time that nicstat is displating stats for in HH:MM:SS format
Int – The interface that the stats to the right are for
rKB/s – Kilobytes/second received
wKB/s – Kilobytes/second transmitted
rPk/s – Packets/second read
wPk/s – Packets/second written
rAvs – Average packet size received
wAvs – Average packet size transmitted
%Util – Percentage that the interface is utilized (differs depending on full or half duplex see the man page)
Sat – This the number of errors/second for the interface – a higher number may indicate the interface is becoming saturated
The x flag shows extended stats:
$ nicstat -x
05:59:36 RdKB WrKB RdPkt WrPkt IErr OErr Coll NoCP Defer %Util
p6p1 25.30 1.64 21.59 15.22 0.00 0.00 0.00 0.00 0.00 0.22
lo 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
These are what those headings mean:
(I could not find a defenition for RdKB, WrKB, RdPkt, WrPkt but from what I have read I believe they equivalent to rKB/s, wKB/s, rPk/s, wPk/s)
-
IErr – Packets received containing errors
OErr – Packets not successfully transmitted because of errors
Coll – Ethernet collisions during transmit
NoCP – When an incoming packet can’nt be sent to the process reading the socket
Defer – Non-collision packets where first transmit attempt was delayed due to the medium being busy
Then there are -t and -u flags:
$ nicstat -t
05:59:40 InKB OutKB InSeg OutSeg Reset AttF %ReTX InConn OutCon Drops
TCP 0.00 0.00 19.53 14.60 0.05 0.00 0.000 0.00 0.18 0.00
$ nicstat -u
06:00:09 InDG OutDG InErr OutErr
UDP 0.50 0.50 0.00 0.00
(InKB, OutKB are the same as rKB/s, wKB/s and InSeg, OutSeg along with InDG, OutDG are the same as rPk/s, wPk/s also InErr, OutErr are the same as IErr, OErr)
-
Reset – The number of times TCP the connection had to be reset
AttF – The number of times the TCP connection has either gone to the CLOSED state or to the LISTEN state
%ReTX – The number of TCP segments transmitted containing one or more previously transmitted octets
InConn – TCP connections have gone to the SYN-RCVD state from the LISTEN state
OutCon – TCP connections have gone to the SYN-SENT state from the CLOSED state
Drops – The total from these three places, completed connection queue, incomplete connection queue, and connections dropped after the initial SYN packet was received
Additionaly you have the a flag which is equivalent to the xtu flags used together. Then there is M and n, which do megabytes instead of kilobytes and does not show the loopback respectivly. My favorite way to run it is with the -aMn flags
$ nicstat -aMn
06:23:08 InKB OutKB InSeg OutSeg Reset AttF %ReTX InConn OutCon Drops
TCP 0.00 0.00 17.42 13.09 0.05 0.00 0.000 0.00 0.17 0.00
06:23:08 InDG OutDG InErr OutErr
UDP 0.47 0.47 0.00 0.00
06:23:08 RdMbps WrMbps RdPkt WrPkt IErr OErr Coll NoCP Defer %Util
p6p1 0.18 0.01 19.43 13.66 0.00 0.00 0.00 0.00 0.00 0.20
You can set an interval, by adding a space then a number after any flags you set, nicstat will display the stats at each interval of the seconds specifide. You can also specify a count, by adding a space then a number after the first number, nicstat will display the stats at each interval of seconds for nuimber of iterations specifide.
Conference Scene
Time: 1:04:45
The Security Bit
Time: 1:11:00
How to Protect your Server Against the Shellshock Bash Vulnerability
https://www.digitalocean.com/community/tutorials/how-to-protect-your-server-against-the-shellshock-bash-vulnerability
SHA-256 SSL Certificates & Why You Need SHA-2
https://www.digicert.com/sha-2-ssl-certificates.htm
Generating a Certificate Signing Request (CSR) using Apache (with mod_ssl) & OpenSSL
http://www.networksolutions.com/support/csr-for-apache-with-mod-ssl-openssl/
Is it Alive?
Time: 1:22:45
Listener Feedback:
show (at) smlr.us or 734-258-7009
Time: 1:27:35
johanv
As you can probably guess, I am not a fan of word processors. I once did HPR episode about this.
Outtro Music
Time: 1:37:10
Balkan Cowboy by Jean Paul Grouve
https://www.jamendo.com/en/track/690344/balkan-cowboy
This content is published under the Attribution-Noncommercial-Share Alike 3.0 Unported license.