cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
563
Views
0
Helpful
2
Replies

ip dhcp snooping database on ftp, is it really needed?

geo555
Level 1
Level 1

Hello fellow Network Engineers,

We have deployed dhcp snooping and partially dai and we are questioning whether we really need to configure dhcp snooping database agent to store the db to ftp.

I know the purpose is for the switch to read the db after it reboots, but from my testings, if the switch reboots, the hosts will send a dhcp request again and the in memory dhcp snooping db will be rebuilt

I read somewhere that is only needed if you have a double supervisor, so that in case of primary sup failure, the backup supervisor will read the db from database. Isn't this synchronized between the two sups?

Also in situations, where you have multiple stacked switches, is the in memory db copied from master to other members?

I appreciate any comments.

thanks,

George E.

 

2 Replies 2

Hello

My understanding is if the master is lost in an existing stack then the new elected master will begin excepting the dhcp packets, As for any failed master/member switch participating in dhcp snooping, Then its bindings are maxed aged, So only what would be lost would be from the switch that failed.

 

If the whole stack failed and reloaded then without a valid DHCP snooping D/B  and with DAI enabled also then communication would be lost until the snoopping D/B is populated again.


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

this does not answer my question.
from my experience, on a switch with DHCP and DAI enabled, when rebooted, all hosts retrasmit a dhcp request, so the database is repopulated.
there is a loss of connection only for couple of seconds until hosts resend the dhcp request.
Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Review Cisco Networking products for a $25 gift card