KB Article #177881
Maximum cv Affected with DIAGI=916 and/or 418
Problem
CFT logs with many Maximum cv Affected error
DIAGI=916
DIAGI=418
Resolution
CFTT09E _ Maximum cv Affected (and complementary messages)
And
CFTT75E connect reject (and complementary messages)
Are indicators about the need to tune both CFT and the partners’ side to avoid both DIAGI 418 and 916
Those two DIAGs error code are related to the fact that when server (418) or when requester (916) the socket- connect has been accepted (networking level and application socket) but the actual tuning cannot handle the PeSIT session.
It makes a lot of non-usable but open network sessions, it reduce the overall bandwidth slowing down a lot other active transfers.
Also, for those errors, the network session is not disconnected before the expiration timer. It will also be never used.
Transfers rescheduled by CFT for 916 errors are delayed and it adds also delay for new request to the same destination.
It affects the same way the remote partner for 418 errors.
For both errors, it reduce dramatically the available bandwidth for other already active transfers
The basics on the sessions tuning when non Multi-node is concerned:
Such errors can be avoided in setting the sessions capabilities with the partner symmetrical so the CNXIN match the partner CNXOUT parameter and the CNXINOUT is equal to the sum of CNXOUT + CNXIN on each side.
The CFT session management, when in multi-node, differs from a stand-alone non-multi-node installation.
In a Multi-node CFT, the session values apply to each nodes and this is to be considered when doing the sessions number adjustment with the partner.
- For a multi-node CFT exchanging with a non-multi-node CFT, the session parameters must be set as in the truth table below:
CFT Multi-node |
CFT non-Multi-node |
CNXOUT=(Partner’ CNXIN) / number of node |
CNXIN = (Partner’ CNXOUT) x Partner’ number of node |
CNXIN=(Partner’ CNXOUT) |
CNXOUT=(Partner’ CNXIN) |
CNXINOUT=CNXIN+CNXOUT |
CNXINOUT=CNXIN+CNXOUT |