Forum Discussion
cpt_ri_F5
Cirrostratus
CirrostratusUDP Datagram LB
Hello,
To enable fair load balancing between backend servers (5 syslog srv >> F5 >> 2 splunk srv)
I created a new udp profile and activated the option : "Datagram LB" : https://support.f5.com/csp/article/K3605
100% of logs received with the default udp profile, but not with the new profile udp (the other parameters are equal)
an idea?
Thanks!
hello,
FYI, I solved this problem with a simple stateless VS: K13675
Thank you all
cpt_ri_F5hello,
FYI, I solved this problem with a simple stateless VS: K13675
Thank you all
boneyardMVP
Thank you for sharing that knowledge.
CA_ValliUDP datagram LB forwards traffic packet-by-packet, and no loger treats UDP packets from the same source and port as part of a connection, so if syslog message is split into multiple packets you might have part of the log on one server and part of the log on the other one, possibly resulting in messages missing.
- cpt_ri_F5
Hello CA_Valli,
Sorry, I don't understand your answer, the stats show approx. 1 million logs received with the default udp profile and approx. 200k with "Datagram LB", there is a loss of logs, isn't it?
Or do you mean in the same entry (with Datagram LB profil), contains several logs?
Thanks!
(Edited by Leslie_Hubertus to tag CA_Valli, to make sure he sees this reply)- CA_Valli
Where are you checking the stats? F5 or splunk? Also is this a live stat or is is a cumulative counter?
What I wanted to point out is that datagramLB changes load balancing behvior, and while "standard" UDP profile keeps track of UDP connection and forwards all packets of the same connection to the same destination, this is no longer true with DLB -- meaning that if a syslog message is split into multiple UDP packets you might end up with some of them being balanced to one pool member and other packets of the same flow being balanced to the second pool member.
I thought that this could be a possible problem, as one splunk server might not be able to reconstruct the full syslog message due to part of it being sent to the other server -- and possibly discarding/not logging the "incomplete" packets.
- cpt_ri_F5
Thank you it's clear
I checked the stats on splunk, cumulative counter (per minute), but it's the same splunk request.
In the splunk graph I see when I change the UDP profile that the number of logs is divided /5 or more
if we can't recover the integrity of the logs, in this case, I don't understand the point of the option "Datagram LB" !
I am interested in another solution to fairly share the logs on the splunk servers
Thanks!