Canon imageRUNNER ADVANCE C255 Series, Service Manual, Page: 756 / 987

COPIER (Service mode for copier) > OPTION (Specification setting mode) > NETWORK
PFWFTPRT 1 Set of RST reply at IP filter FTP SEND
Detail *Operation on this item is restricted by the setting of [Restrict Service Representation Access].
When FTP SEND is executed using an IP filter by which packets from a specific remote PC are
rejected, SYN is returned to the port 113 if the PC supports authentication of the FTP port 113.
However, since the IP filter blocks the packets, the block logs are increased and the performance
is lowered.
When 1 is set, RST is returned to the port 113 without blocking packets.
Use Case When executing FTP SEND against the OS which supports authentication of the FTP port 113
while the IP filter is enabled
Adj/Set/Operate Method Enter the setting value, and then press OK key.
Display/Adj/Set Range 0 to 1
0: OFF, 1: ON
Default Value 0
IPMTU 1 Setting of MTU size
Detail To set MTU size of network packet.
This item is used when performing SEND communication between locations connected with
Ethernet in a field environment where MTU black hole problem occurs.
Use Case
When MTU black hole problem occur
Adj/Set/Operate Method
Enter the setting value, and then press OK key.
Caution
With IPv6, use of MTU which size is less than 1280 bytes is not recommended by RFC.
Therefore, when setting IPv6 to ON and MTU to 7 or smaller, communication using IPv6 may not
be available.
Display/Adj/Set Range
1 to 10
1: 600 byte, 2: 700 byte, ..., 9: 1400 byte, 10: 1500 byte
Unit
byte
Default Value 10
Supplement/Memo MTU: The maximum size of data unit that can be transmitted with a single transfer (1 frame) over
network.
MTU black hole: A problem which occurs when ICMP packets are filtered by firewall, etc. (Since
no message is sent to the sender, the sender does not notice that the packets are discarded and
timeout occurs.)
Amount of Change per
Unit
100
DDNSINTV 1 Set of DDNS periodical update interval
Detail DNS registration is executed only once at start-up with the current iR, so the registered contents
are deleted in an environment where the DNS server settings are deleted at intervals.
To set the interval of DDNS periodical update for not deleting the registered contents.
Use Case When the DNS server settings are deleted at intervals
Adj/Set/Operate Method Enter the setting value, and then press OK key.
Display/Adj/Set Range 0 to 48
0: No periodical update, 1: 1-hour interval, 2: 2-hour interval, ..., 47: 47-hour interval, 48: 48-hour
interval
Default Value
24
8. Service Mode
745