(TIL) Today I Learned...

Started by Seittit, January 13, 2015, 03:50:21 AM

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javentre

#60
February 17, 2015, 04:01:13 PM
re:  WAAS

I'm very please with my Silverpeak units, they've been fairly trouble free and I really push a lot of data through them (multi gbps).
[url="http://networking.ventrefamily.com"]http://networking.ventrefamily.com[/url]

Seittit

#61
February 18, 2015, 12:00:32 PM
TIL Traceroute uses UDP because in 1988 Router Vendors implemented the RFC's incorrectly

"Traceroute is unique because it enlists the help of both UDP and ICMP. UDP was used because when the tool was first created in 1988 router vendors had misinterpreted the RFC's. The RFC's state that you should never respond to an an ICMP error packet. Router vendors implemented this as "never respond to any ICMP packets." So when traceroute was developed in 1988 UDP had to be used in order to elicit a consistent reply. Today traceroute can be used with the "-I" switch in order to generate Echo-Request packets rather than UDP packets. In this mode it functions identically to Windows tracert."

Source: Quote from GIAC Certified Perimeter Protection Analyst (GPPA) SEC502 Book 502.1 pg 195

deanwebb

#62
February 18, 2015, 01:46:59 PM
I did not know that, cool.

TIL that my PM *still* hasn't called together the big meeting between different groups to resolve the wireless pop-up issue due to us standing up a new RADIUS server... but will still bug out when I say the project is delayed due to that meeting not having happened yet to approve the changes necessary. Not my job to call that meeting, just my job to explain the tech stuff...
Take a baseball bat and trash all the routers, shout out "IT'S A NETWORK PROBLEM NOW, SUCKERS!" and then peel out of the parking lot in your Ferrari.
"The world could perish if people only worked on things that were easy to handle." -- Vladimir Savchenko
Вопросы есть? Вопросов нет! | BCEB: Belkin Certified Expert Baffler | "Plan B is Plan A with an element of panic." -- John Clarke
Accounting is architecture, remember that!
Air gaps are high-latency Internet connections.

wintermute000

#63
February 18, 2015, 02:21:00 PM
Hahahahaha yes UDP traceroutes have been the bane of many junior fw admins (or in my experience what HP deems a 'firewall admin' = person who failed CCENT)

Seittit

#64
February 18, 2015, 04:52:04 PM
today my coworker discovered not to run a show-tech through the console on a Nexus 7k running several contexts.

the funny factor is that he's doing it all in comic sans.

icecream-guy

#65
February 19, 2015, 07:27:19 AM
(meeting ran late so I couldn't post a TIL)

well YIL,  had a 2 1/2 hour discussion with Cisco about the 9K's and how ACI works, with demo.  barely chipped the iceberg, planning a deep dive next week to get more details.  But it looks pretty cool.
:professorcat:

My Moral Fibers have been cut.

deanwebb

#66
February 19, 2015, 08:28:16 AM
TIL that video conferences fall flat when one of the rooms participating doesn't have video gear installed yet.
Take a baseball bat and trash all the routers, shout out "IT'S A NETWORK PROBLEM NOW, SUCKERS!" and then peel out of the parking lot in your Ferrari.
"The world could perish if people only worked on things that were easy to handle." -- Vladimir Savchenko
Вопросы есть? Вопросов нет! | BCEB: Belkin Certified Expert Baffler | "Plan B is Plan A with an element of panic." -- John Clarke
Accounting is architecture, remember that!
Air gaps are high-latency Internet connections.

deanwebb

#67
February 19, 2015, 02:41:44 PM
TI also L that although our voice traffic is marked ef outbound from this location, it can return with a variety of markings on the way back, including "best effort."
Take a baseball bat and trash all the routers, shout out "IT'S A NETWORK PROBLEM NOW, SUCKERS!" and then peel out of the parking lot in your Ferrari.
"The world could perish if people only worked on things that were easy to handle." -- Vladimir Savchenko
Вопросы есть? Вопросов нет! | BCEB: Belkin Certified Expert Baffler | "Plan B is Plan A with an element of panic." -- John Clarke
Accounting is architecture, remember that!
Air gaps are high-latency Internet connections.

Mowery

#68
February 19, 2015, 04:09:30 PM
TIL no matter how many times you verify with a SP, if their tech shows up without the proper equipment, no circuit will be activated.
QuoteYeah, right... and 96% of the Internet being dark and mysterious? How about 96% of the internet being Cisco web pages I can never find when I need them...

Seittit

#69
February 19, 2015, 04:32:01 PM
TIL never to trust the wireless guys for EIGRP configuration.

Exhibit A:
Code Select
router eigrp 100
network 10.0.0.0
neighbor 10.255.255.8 Vlan654
neighbor 10.255.255.10 Vlan654
neighbor 10.255.255.12 Vlan654
neighbor 10.255.255.14 Vlan654
neighbor 10.255.255.16 Vlan654
neighbor 10.255.255.18 Vlan654
neighbor 10.255.255.20 Vlan654
neighbor 10.255.255.22 Vlan654
neighbor 10.255.255.24 Vlan654
neighbor 10.255.255.26 Vlan654
neighbor 10.255.255.28 Vlan654
neighbor 10.255.255.30 Vlan654
neighbor 10.255.255.32 Vlan654
neighbor 10.255.255.34 Vlan654
neighbor 10.255.255.36 Vlan654
neighbor 10.255.255.38 Vlan654
neighbor 10.255.255.40 Vlan654
neighbor 10.255.255.42 Vlan654
neighbor 10.255.255.44 Vlan654
neighbor 10.255.255.46 Vlan654
neighbor 10.255.255.48 Vlan654
neighbor 10.255.255.50 Vlan654
neighbor 10.255.255.52 Vlan654
neighbor 10.255.255.54 Vlan654
neighbor 10.255.255.56 Vlan654
neighbor 10.255.255.58 Vlan654
neighbor 10.255.255.60 Vlan654
neighbor 10.255.255.62 Vlan654
neighbor 10.255.255.64 Vlan654
neighbor 10.255.255.66 Vlan654
neighbor 10.255.255.68 Vlan654
neighbor 10.255.255.70 Vlan654
neighbor 10.255.255.72 Vlan654
neighbor 10.255.255.74 Vlan654
neighbor 10.255.255.76 Vlan654
neighbor 10.255.255.78 Vlan654
neighbor 10.255.255.80 Vlan654
neighbor 10.255.255.82 Vlan654
neighbor 10.255.255.84 Vlan654
neighbor 10.255.255.86 Vlan654
neighbor 10.255.255.88 Vlan654
neighbor 10.255.255.90 Vlan654
neighbor 10.255.255.92 Vlan654
neighbor 10.255.255.94 Vlan654
neighbor 10.255.255.96 Vlan654
neighbor 10.255.255.98 Vlan654
neighbor 10.255.255.100 Vlan654
neighbor 10.255.255.102 Vlan654
neighbor 10.255.255.104 Vlan654
neighbor 10.255.255.106 Vlan654
neighbor 10.255.255.108 Vlan654
neighbor 10.255.255.110 Vlan654
neighbor 10.255.255.112 Vlan654
neighbor 10.255.255.114 Vlan654
neighbor 10.255.255.116 Vlan654
neighbor 10.255.255.118 Vlan654
neighbor 10.255.255.120 Vlan654
neighbor 10.255.255.122 Vlan654
neighbor 10.255.255.124 Vlan654
neighbor 10.255.255.126 Vlan654
neighbor 10.255.255.128 Vlan654
neighbor 10.255.255.130 Vlan654
neighbor 10.255.255.132 Vlan654
neighbor 10.255.255.134 Vlan654
neighbor 10.255.255.136 Vlan654
neighbor 10.255.255.138 Vlan654
neighbor 10.255.255.140 Vlan654
neighbor 10.255.255.142 Vlan654
neighbor 10.255.255.144 Vlan654
neighbor 10.255.255.146 Vlan654
neighbor 10.255.255.148 Vlan654
neighbor 10.255.255.150 Vlan654
neighbor 10.255.255.152 Vlan654
neighbor 10.255.255.154 Vlan654
neighbor 10.255.255.156 Vlan654
neighbor 10.255.255.158 Vlan654
neighbor 10.255.255.160 Vlan654
neighbor 10.255.255.162 Vlan654
neighbor 10.255.255.164 Vlan654
neighbor 10.255.255.166 Vlan654
neighbor 10.255.255.168 Vlan654
neighbor 10.255.255.170 Vlan654
neighbor 10.255.255.172 Vlan654
neighbor 10.255.255.174 Vlan654
neighbor 10.255.255.176 Vlan654
neighbor 10.255.255.178 Vlan654
neighbor 10.255.255.180 Vlan654
neighbor 10.255.255.182 Vlan654
neighbor 10.255.255.184 Vlan654
neighbor 10.255.255.186 Vlan654
neighbor 10.255.255.188 Vlan654
neighbor 10.255.255.190 Vlan654
neighbor 10.255.255.192 Vlan654
neighbor 10.255.255.194 Vlan654
neighbor 10.255.255.196 Vlan654
neighbor 10.255.255.198 Vlan654
neighbor 10.255.255.200 Vlan654
neighbor 10.255.255.202 Vlan654
neighbor 10.255.255.204 Vlan654
neighbor 10.255.255.206 Vlan654
neighbor 10.255.255.208 Vlan654
neighbor 10.255.255.210 Vlan654
neighbor 10.255.255.212 Vlan654
neighbor 10.255.255.214 Vlan654
neighbor 10.255.255.216 Vlan654
neighbor 10.255.255.218 Vlan654
neighbor 10.255.255.220 Vlan654
neighbor 10.255.255.222 Vlan654
neighbor 10.255.255.224 Vlan654
neighbor 10.255.255.226 Vlan654
neighbor 10.255.255.228 Vlan654
neighbor 10.255.255.230 Vlan654
neighbor 10.255.255.232 Vlan654
neighbor 10.255.255.234 Vlan654
neighbor 10.255.255.236 Vlan654
neighbor 10.255.255.238 Vlan654
neighbor 10.255.255.240 Vlan654
neighbor 10.255.255.242 Vlan654
neighbor 10.255.255.244 Vlan654
neighbor 10.255.255.246 Vlan654
neighbor 10.255.255.248 Vlan654
neighbor 10.255.255.250 Vlan654
neighbor 10.255.255.252 Vlan654
neighbor 10.255.255.254 Vlan654
passive-interface default
no passive-interface Vlan654
no passive-interface GigabitEthernet0/1
no passive-interface GigabitEthernet0/2


Actual EIGRP peers:
Code Select
PMPrt1#sh ip eigrp neigh
EIGRP-IPv4 Neighbors for AS(666)
H   Address                 Interface              Hold Uptime   SRTT   RTO  Q  Seq
                                                   (sec)         (ms)       Cnt Num
2   10.255.255.8             Vl654                    12 00:00:30    1  5000  1  0
1   10.255.103.212          Gi0/2                    10 23w1d      29   174  0  341843
0   10.255.103.201          Gi0/1                    12 23w2d       7   100  0  654733

deanwebb

#70
February 19, 2015, 04:56:51 PM
TIL that certificates are DAMN tricky, a damn sight more tricky than I thought...
Take a baseball bat and trash all the routers, shout out "IT'S A NETWORK PROBLEM NOW, SUCKERS!" and then peel out of the parking lot in your Ferrari.
"The world could perish if people only worked on things that were easy to handle." -- Vladimir Savchenko
Вопросы есть? Вопросов нет! | BCEB: Belkin Certified Expert Baffler | "Plan B is Plan A with an element of panic." -- John Clarke
Accounting is architecture, remember that!
Air gaps are high-latency Internet connections.

icecream-guy

#71
February 20, 2015, 07:48:01 AM
Quote from: Seittit on February 19, 2015, 04:32:01 PM
TIL never to trust the wireless guys for EIGRP configuration.

Exhibit A:
Code Select
router eigrp 100
network 10.0.0.0
neighbor 10.255.255.8 Vlan654
neighbor 10.255.255.10 Vlan654
neighbor 10.255.255.12 Vlan654
neighbor 10.255.255.14 Vlan654
neighbor 10.255.255.16 Vlan654
neighbor 10.255.255.18 Vlan654
neighbor 10.255.255.20 Vlan654
neighbor 10.255.255.22 Vlan654
...
<snip>



WTF ????
:professorcat:

My Moral Fibers have been cut.

deanwebb

#72
February 20, 2015, 09:10:00 AM
TIL even more about certificates, and I solved my problem with them! Well, one of my problems... at least the production wireless will be ready for the new RADIUS back-end come Monday. Guest wireless, not so much right now...
Take a baseball bat and trash all the routers, shout out "IT'S A NETWORK PROBLEM NOW, SUCKERS!" and then peel out of the parking lot in your Ferrari.
"The world could perish if people only worked on things that were easy to handle." -- Vladimir Savchenko
Вопросы есть? Вопросов нет! | BCEB: Belkin Certified Expert Baffler | "Plan B is Plan A with an element of panic." -- John Clarke
Accounting is architecture, remember that!
Air gaps are high-latency Internet connections.

icecream-guy

#73
February 20, 2015, 12:13:00 PM
TIL I learned about IXIA network tools, in particular the BreakingPoint application and testing solution, in a nice 2 hours meeting with the IXIA pre-sales team.  We should be getting one to demo soon.
:professorcat:

My Moral Fibers have been cut.

Seittit

#74
February 20, 2015, 02:39:42 PM
TIL how many papers need to be signed to close on a new house.

Wowsers, my right hand feels like it's recovering from a ten hour fap-a-thon
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