Finn,

I don't know about manual starts of the client but for scheduled events
the parameters MAXCMDRETRIES and RETRYPERIOD work together to
control the number of times a client scheduler attempts to contact the server
if the server is not responding - for whatever reason - at the allotted
scheduled time. The client establishes that a connection cannot be made ( this
in itself may take some time depending on O/S and network setup ) then counts
down Retryperiod minutes, attempts to reconnect - if it fails
it then counts down Retryperiod minutes and attempts again. This it does
Maxcmdretries times. Note that these parameters only manage the behaviour
of client schedules that have not yet started to backup or schedules that
have completed the backup and are attempting to report the results back to
the server. Note also that these parameters can be set at the server end
as well and if so, override the settings at the client end.

If a scheduled session has already started and is interupted - for example
network outage - the Commrestartduration and Commrestartinterval
parameters specify the number of minutes and the interval in seconds that
the client should attempt to reconnect. These are set just at the
client end.

Note that the operation of these parameters can mean that a scheduled
backup can take place *outside* of the scheduled backup window at the
server - something we've found difficult to handle. The 4.1 client
documentation does say something about "the schedule fails if a communication
failure occurs and the client cannot reconnect with the server before the
startup window for the schedule ends". However, this is wrong - the schedule
status in the events table now gets set to restarted at the server and the
schedule will complete - this is documented by  PC44954 anAPARs IC31350 and
IC31464.

This behaviour can be a complete pain if for example, your server hangs
midway through a bunch of scheduled client backup sessions, you
restart the server and probably want to do something to redress the
conditions that caused the hang - maybe a BACKUP DB or MIGRATION or or ..
however, clients retrying and reconnecting to start or restart their backups
can seriously interfere with this. The solution is to set the
MAXCMDRETRIES to zero or RETRYPERIOD to something like 0 and 720 - this will
give you 12 hours free of client retries - and set COMMRESTARTDURATION to
something small.

HTH
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Ian Smith
Ian Smith
Oxford University Computing Services, Oxford, UK.