Netscaler 10.1 Some Services Listed as Down then Up one Second Later

On our Netscaler 10.1 I have noticed from from time to time services will be listed as down then up one second later. This is not protocol specific. The monitors being used are the in box TCP, http to https.  I noticed some of the monitor responce time are very high but from my understanding this is not a ping responce time by more of round trip time that is protocal specific. Any suggestions on how I can find our why the services are going up and down. Also the servers event logs are not showing any problems.
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Dirk KotteSECommented:
are there a firewall between netscaler and backend services?
possible some packets are dropped.
is the NS virtual (VPX)? The time might jitter.
You can capture the traffic to this services with dcpdump and analyze externally.
compdigit44Author Commented:
Thanks for getting  back to me...
1) NO firewall in-between Netscaler and backend servers (this is used internally)
2) We are using a Netscaler 10.1 MPX 10500
3) So monitors should high responce stills for http services as an example but this is not a like a ping but more of a protocl round-time time if I understand it correctly yet some of these numbers can get very high as in 20000ms
Dirk KotteSECommented:
3. i think 20 seconds are too big.
that my be the timeout set at the netscaler, but not your really RTT.

NS may monitor some webpages or webshops and there may be a RTT from some seconds, but internally your response-time should be shorter. especially with (xenapp/xendesktop)  

Which services have the high responce time?

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compdigit44Author Commented:
We are using the default monitors for http, https, tcp etc...

Any suggestion on what could cause this??? The Netscaler was setup by the previous admin to use LACP if this makes a difference but has been set like this for 2+ years now
Dirk KotteSECommented:
go to the switch and check the LACP status.
compdigit44Author Commented:
Thank you for the feed back. I do not have access to the switch which is managed by our Network Team. For my own know what would they be looking for???
Dirk KotteSECommented:
ask them!
network guys own a deep knowledge about their devices mostly...  
- LACP - status
- last LACP connect time
- errors
- LACP renegotation
- LACP disconnects

also an option: try to disconnect one LINK ... possible the connection is dead afterwards or more stable :-)
(i need a downtime for such a test)
compdigit44Author Commented:
Thank you very much since I never have setup LACP myself I am interested to see what they find if anything. I will keep you posted
compdigit44Author Commented:
My network team got back to me and said the LACP setup on the switch is correct and not showing and problems it is set for fix algorithm if that helps you at all
Dirk KotteSECommented:
but ask your network team, if the logical LACP interface is up and frames are counted.

as a simple test i would disconnect one link, so LACP can`t be established and LACP related problems should not occur.
compdigit44Author Commented:
They confirmed the LACP interface is up and are counted.... Any other suggestions... Could it be the build we are on..

10.1 build 128.8????
compdigit44Author Commented:
I opened a support ticket with Citrix and post there findings on this..
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