Just be careful with withdraws and re-announcements frequently. You may
trigger your upstream's flap protection, damping, etc. Every carrier we
peer with does it. AT&T is the most aggressive at policing
advertisements based on my past experience a couple years ago, and I
highly doubt they've toned it down any. Had a power issue at a site and
our router rebooted a couple times in 5 minutes. They wouldn't take our
advertisement anymore. Took seven freakin hours to get an engineer to
clear it. So, try not to shoot yourself in the foot.
On 9/9/2016 9:12 AM, Faisal Imtiaz wrote:
simple....
Adding routes and removing routes is a defined bgp function, and it is
considered to be one of a softer impact...
killing a bgp session is disruptive, unexpected, depending on
timeouts, it can take as long a 3min to determine if the peer is gone,
and then another few min for the routes to fully propagate across the
internet.. meanwhile traffic is still heading your way...
Regards
Faisal Imtiaz
Snappy Internet & Telecom
7266 SW 48 Street
Miami, FL 33155
Tel: 305 663 5518 x 232
Help-desk: (305)663-5518 Option 2 or Email: [email protected]
------------------------------------------------------------------------
*From: *"Josh Luthman" <[email protected]>
*To: *[email protected]
*Sent: *Friday, September 9, 2016 10:01:24 AM
*Subject: *Re: [AFMUG] Bgp automatic drop session?
Oh well that's easy enough. Why is that better than disabling the
peer?
Josh Luthman
Office: 937-552-2340
Direct: 937-552-2343
1100 Wayne St
Suite 1337
Troy, OH 45373
On Fri, Sep 9, 2016 at 9:58 AM, Faisal Imtiaz
<[email protected] <mailto:[email protected]>> wrote:
This goes back to best practices...
you should be using a filter to advertise the routes...
e.g. our hiq-out filter .....
0 chain=hiq-out match-chain=SDF-11280 invert-match=no
action=accept set-bgp-prepend=2 set-bgp-prepend-path=""
1 X chain=hiq-out match-chain=SDG-10302
bgp-communities=11280:115 invert-match=no action=accept
set-bgp-prepend=3 set-bgp-prepend-path=""
2 chain=hiq-out match-chain=TNN-46215
bgp-communities=11280:115 invert-match=no action=accept
set-bgp-prepend-path=""
3 chain=hiq-out bgp-communities=11280:245 invert-match=no
action=accept set-bgp-prepend-path=""
4 X chain=hiq-out bgp-communities=11280:135 invert-match=no
action=accept set-bgp-prepend-path=""
5 chain=hiq-out bgp-communities=11280:666 invert-match=no
action=accept set-bgp-prepend-path=""
6 X chain=hiq-out bgp-as-path=^29846_*
bgp-communities=11280:235 invert-match=no action=accept
set-bgp-prepend-path=""
7 chain=hiq-out invert-match=no action=discard
set-bgp-prepend-path=""
As you can see a couple of chain's are disabled (X)..... that
will withdraw the prefixes as defined in referenced chains.
Regards.
Faisal Imtiaz
Snappy Internet & Telecom
7266 SW 48 Street
Miami, FL 33155
Tel: 305 663 5518 x 232 <tel:305%20663%205518%20x%20232>
Help-desk: (305)663-5518 <tel:%28305%29663-5518> Option 2 or
Email: [email protected]
------------------------------------------------------------------------
*From: *"Josh Luthman" <[email protected]
<mailto:[email protected]>>
*To: *[email protected] <mailto:[email protected]>
*Sent: *Friday, September 9, 2016 9:50:20 AM
*Subject: *Re: [AFMUG] Bgp automatic drop session?
How would you "withdraw routes" on a Mikrotik?
Josh Luthman
Office: 937-552-2340 <tel:937-552-2340>
Direct: 937-552-2343 <tel:937-552-2343>
1100 Wayne St
Suite 1337
Troy, OH 45373
On Fri, Sep 9, 2016 at 9:47 AM, Faisal Imtiaz
<[email protected]
<mailto:[email protected]>> wrote:
Tut tut Tut ......
let's not start with bad habits...
Best practices would be to withdraw the routes, and
not kill the bgp session...
:)
Faisal Imtiaz
Snappy Internet & Telecom
7266 SW 48 Street
Miami, FL 33155
Tel: 305 663 5518 x 232 <tel:305%20663%205518%20x%20232>
Help-desk: (305)663-5518 <tel:%28305%29663-5518>
Option 2 or Email: [email protected]
------------------------------------------------------------------------
*From: *"TJ Trout" <[email protected]
<mailto:[email protected]>>
*To: *[email protected] <mailto:[email protected]>
*Sent: *Friday, September 9, 2016 1:31:10 AM
*Subject: *[AFMUG] Bgp automatic drop session?
Does anyone run any type of script that will
automatically drop a bgp session when a upstream
is having problems but isn't hard down ? Like
packet loss, high latency or low throughout?
I'm assuming it's nearly impossible without human
intervention??
