FAQ

The differences from NS-2240 are as follows.
【H/W】
-There are three models like 16/32/48 ports. (Please use NS-2240-04 if you need 4 ports model.)
-NS-2250 has the redundant AC power supplies as standard. (DC power supply is not redundant.)
-The clamp instead of the metal fitting is bundled to fix the power cable.
-The AC power cable and above clamp are bundled. (2 sets each)
-There are 2 ports of 10/100/1000Base-Tx and they support auto MDI/MDI-X.
-The LED of LAN port are changed to mean Speed and LINK/ACT.
-The USB memory is bundled to store settings instead of CF card. (It can not be inserted and ejected during read and write.)
-DSR lamp is deleted, and Tx and Rx lamps are added in the serial ports.
-The LED in the console port is deleted.
-The temperature sensor is supported in all models.
【Specifications】
-Dimensions　W426mm/D262mm/H44mm (Depth is 38mm longer)
-Weight About 3.4kg (0.4kg heavier)
-Maximum power consumption AC100-240V：About 17W, DC-48V：About 15W (slightly increased)
【Manual】
-Only downloading from Home Page. The bundled CD is deleted.
【System Software】
-Shorter startup time
-The "configure" commands are deleted.
-The specification of "write" command is changed. (The setting is stored in both internal and external startup file)
-Power trap and link down trap are added.
-FTP client function is added.
-"disconnect" command (ftp/ftpd/sftpd/portd) is expanded.
-The function of restore/backup system full image is added.
-Default timezone is changed to "UTC" from "JST"
-Default setting of detect_dsr is changed to "off"
-CF is deleted and FLASH is added from port logs storage.
There are some more differences in "show" commands and setting commands.
Please refer to Instruction Manual and Command Reference for details.

The maximum values of power consumption, consumption current, calorific value and British thermal unit of NS-2250 are as follows.
【Power consumption】
AC100V:17W
AC240V:17W
DC-48V:15W
【Consumption current】
AC100V:0.32A
AC240V:0.18A
DC-48V:0.30A
【Calorific value】
AC100V:14.62kcal/h
AC240V:14.62kcal/h
DC-48V:12.89kcal/h
【British thermal unit】
AC100V:58.0BTU/h
AC240V:58.0BTU/h
DC-48V:51.18BTU/h

When using with other than AC100V, please prepare the following AC power cable and use it.
・NS-2250 side
Plug-in type 2-pin connector with ground terminal : IEC60320 C-13 10A-250V
・Outlet side
Please use the 10A - 250V cable matching the outlet shape of the installation environment.

If you lost the connector jig, please contact us or the distributor you bought this device from.
If you use the connector jig other than the bundled one, an equipment failure or accident may occur.

The setting files of NS-2250 are stored in the bundled USB memory.
When NS-2250 fails, you can easily make it recover after replacing it and insert USB memory you have used.
Since the bundled USB memory is exclusive for NS-2250, it can not read and write on a personal computer and also the USB memory on the market is not usable.

The MTBF/MTTR/Rate of Operation of NS-2250 are as follows.
MTBF: 100,000 hours
MTTR: 1 hour
Rate of Operation: 99.99%
※The calculation formula of the Rate of Operation is (MTBF/(MTBF+MTTR)).

LAN port can be used as a port of 10BASE-T/100BASE-TX/1000BASE-T. And MDI/MDI-X Auto Negotiation is supported.

【When the bonding function is disabled】
Two LAN ports are available in different segments.
For example, LAN1 is 192.168.1.1/24 and LAN2 is 192.168.2.1/24.
When you use LAN ports redundantly, please set 2 routings that define the priority (metric). If you omit the metric, the value "0"(high-priority) is set automatically.
　[high-priority:LAN1] # create ip route 0.0.0.0/0 gateway 192.168.1.254
　[low-priority:LAN2] # create ip route 0.0.0.0/0 gateway 192.168.2.254 metric 100

When the link down of the priority port is detected, the route is switched.

【When the bonding function is enabled】
The virtual interface "bond1" is generated and the IP address is defined only for bond1.
It operates as fault tolerance(Active/Backup), and when LAN1 is linked up LAN1 becomes Active port preferentially.
When the link down of the Active port is detected, Active and Backup are switched.

To access the managed equipment connected to the serial port of NS-2250, you use "Telnet" command or the software such as "TeraTerm" on the operating PC, you operate.
NS-2250 can be accessed by SSH client.

There are 2 methods to access the monitored equipment as follows.
Direct mode:
You specify the number of TCP port directly.
Select mode:
After log in NS-2250 using TELNET/SSH client, you can access the managed equipment to select the number of port from "port select menu".
[The following is the operation on the operating PC you operate]

[In the case of the direct mode]

> telnet 192.168.1.1(The IP address of SmartCS) 8101
(Directly specify the TCP port number.)
-------------------------------
Host : "SmartCS1"
Label : "router1"
-------------------------------
1 : display Port Log
2 : display Port Log (LAST)
3 : start tty connection
4 : close telnet/ssh session
5 : show all commands
tty-1:rw>; 3↓
Press "CTRL-C" to return this MENU.
Start tty connection

XXXXX login:　(The "login:" prompt of the monitored equipment.)

[In the case of the select mode]

>telnet 192.168.1.1(The IP address of SmartCS)

login: portuser1　(Log in using the port user name.)
Password:

*The above is the contents displayed in the port user authentication screen.
The port user authentication function must be enabled when you use the select mode.
Host : "SmartCS1"
login from 192.168.1.10
user (portuser1) Access TTY List
===========================================================================
tty : Label 　RW　RO
---------------------------------------------------------------------------
1 : router1 　---　---
2 : switch-1　---　---
3 : switch-2　---　---
(Omitted)
32 : server-X ---　---
---------------------------------------------------------------------------
Enter tty number to access serial port
[ttyno] : connect to serial port RW session ( 1 - 32 )
[ttyno]r : connect to serial port RO session ( 1r - 32r )
l 　　　　 : show tty list
l[ttyno]-[ttyno] : show a part of tty list
d : show detail tty list
d[ttyno]-[ttyno] : show a part of detail tty list
h : help message
e : exit
===========================================================================
tty>1 (Specifying the serial port number you want to connect from the above port
server menu.)
connect tty 1 RW mode

-------------------------------
Host : "SmartCS1"
Label : "router1"
-------------------------------
0 : return Port Select Menu
1 : display Port Log
2 : display Port Log (LAST)
3 : start tty connection
4 : close telnet/ssh session
5 : show all commands
tty-1:rw>3↓
Press "CTRL-C" to return this MENU.
Start tty connection

XXXXX login:　(The "login:" prompt of the monitored equipment.)



Please refer to "Chapter 4 Settings" of the Instruction Manual about the setting.

You can access NS-2250 and the equipment connected to the serial port via SSH.
The specifications of SSH are as follows.

Protocol : SSH Version 2(RFC4250-4254, 4256)
Authentication method : Password authentication(Basic), Public key authentication
Public key :
RSA encryption key(Key length : Max 4096bit)
DSA encryption key(Key length : 1024bit)
ECDSA encryption key(Key length : 128/256/521bit)
Encryption method : 3DES/Blowfish/AES

The shape of the serial port of NS-2250 is RJ45.
Please refer to the following Cabling Reference about the serial cable and conversion connector used for NS-2250.

We sell 2 types of DB9-RJ45 conversion connector "NS-490" and "NS-354".
Both of them are the set of 4 connectors.
About the circuit of the conversion connector, please refer to "Appendix B" of the Installation Manual.
The conversion connector screws sold by us are inch screws.

When flow control function enabled, even if all serial ports are set to 115 kbps, data can not be missed.
When flow control function disabled, please use all serial ports set from 9600bps-57600bps as much as possible.
When using all serial ports set to 115kbps, if the transferred data is a small amount the data can not be missed.
But if the baud rate of all serial ports is set to 115kbps the data can be missed.

The maximum length of the serial cable is defined to satisfy an electrostatic capacity within 2500pF in RS232 standard（ANSI/TIA-232-F).
The maximum length is about 50 meters calculating based on the line-to-line capacitance of general Cat5e UTP cable (about 30 pF / m measured by our company) and the stray capacitance 15pF/m.
However, this can not be guaranteed because it also depends on the using environment and connected equipment.
If you use the long serial cable please check in advance.

The command log is stored in NS-2250.
By connecting a equipment that does not support command log to this equipment, it is possible to store the executed command and its display result.

The storage capacity varies depending on whether RAM or internal FLASH memory is used or not.

In case of storing in RAM :
The maximum capacity of port logs stored in NS-2250 is as follows.
*NS-2250-16/16D:　 8MByte
*NS-2250-32/32D:　16MByte
*NS-2250-48/48D:　24MByte
The setting range of the capacity of port logs stored per serial port of NS-2250 is as follows.
*All models:　100KByte-2MByte（Default: 500KByte）


In case of storing in the internal FLASH :
The maximum capacity of port logs stored in NS-2250 is as follows.
*NS-2250-16/16D:　48MByte
*NS-2250-32/32D:　96MByte
*NS-2250-48/48D:　144MByte
The setting range of the capacity of port logs stored per serial port of NS-2250 is as follows.
*ALL models:　100KByte-8MByte（Default: 3MByte）

It is possible. The following time stamp is put into the logs.
＜Mon Sep 14 17:42:38 JST 2015＞　＜- (Time stamp)
ether: port 1 LINK DOWN
ether: port 2 LINK DOWN
ether: port 3 LINK DOWN
ether: port 4 LINK DOWN

＜Mon Sep 14 17:43:38 JST 2015＞ ＜- (Time stamp)
ether: port 1 LINK UP 100M FULL
ether: port 2 LINK UP 100M FULL
ether: port 3 LINK UP 100M FULL
ether: port 4 LINK UP 100M FULL

The logs can be transferred to the specified Mail/FTP/NFS/Syslog server.
Please refer to "Chapter 4 Settings" of the Instruction Manual about the setting.

You can intentionally send break signals by using port server menu or client software like TeraTerm.
However, the break character needs to be set in advance to relay the break signal.

Please refer to "Chapter 7.1 Port server menu command" of the Command Reference and "Chapter 4.4.10 Configure other port server functions" of the Instruction Manual for details.

NS-2250 supports RADIUS and TACACS+ authentication.
Since it does not support LDAP authentication, LDAP authentication must be performed via RADIUS or TACACS+ server.

NS-2250 supports SNMP Version2 and sends the following Traps.
*Coldstart Trap
*Link Up/Down Trap
*Authentication Failure Trap
*Serial DSR Trap
*Power Trap
*Bonding Active Switch Trap
Please refer to "Chapter 2.4 Operation management functions" of the Instruction Manual for details.

You can not store syslog etc. which is built in Unix or Linux, but enhanced syslog-ng can be stored.
The following is an example of setting when using syslog-ng-1.6.12-1 in Fedora Core.
Please refer to the manual of syslog-ng about the details of the setting file and parameters.

Moreover, please refer to one of the followings about the specific syslog-ng.conf.
(a) For V1.6 series　syslog-ng.conf.SmartCS
(b) For V3.2 series　syslog-ng.conf.SmartCS

（1）The setting of syslog-ng

・Installing syslog-ng
# yum install syslog-ng*

・Switch the starting Syslog server package from syslog to syslog-ng
# /sbin/chkconfig syslog off
# /sbin/chkconfig syslog-ng on

・Make sure that syslog is disabled
# /sbin/chkconfig --list syslog
syslog 0:off 1:off 2:off 3:off 4:off 5:off 6:off

・Make sure that syslog-ng is enabled
# /sbin/chkconfig --list syslog-ng
syslog-ng 0:off 1:off 2:on 3:on 4:on 5:on 6:off

・Back up the original of syslog-ng.conf
# cp /etc/syslog-ng/syslog-ng.conf /etc/syslog-ng/syslog-ng.conf.org

・Copy syslog-ng.conf.SmartCS to syslog-ng.conf
# cp /etc/syslog-ng/syslog-ng.conf.SmartCS /etc/syslog-ng/syslog-ng.conf

・Finish syslog
# /etc/init.d/syslog stop

・Start syslog-ng
# /etc/init.d/syslog-ng start

On the switched syslog-ng server, the port log and Syslog of NS-2250 are saved as follows.
# ls -la /var/log
-rw------- 1 root root 　　24185 2月 18 10:51 10.5.31.175-sys.log
-rw------- 1 root root 16012143 2月 13 13:10 10.5.31.175-tty1-port.log
-rw------- 1 root root 16128000 2月 13 14:51 10.5.31.175-tty10-port.log
-rw------- 1 root root 16128000 2月 13 14:52 10.5.31.175-tty11-port.log
-rw------- 1 root root 　7971894 2月 15 13:19 10.5.31.175-tty12-port.log
-rw------- 1 root root 　3910221 2月 15 12:45 10.5.31.175-tty15-port.log
-rw------- 1 root root 15595272 2月 　8 22:26 10.5.31.175-tty18-port.log
-rw------- 1 root root 　8064000 2月 13 14:24 10.5.31.175-tty2-port.log
-rw------- 1 root root 　4032000 2月 13 12:39 10.5.31.175-tty24-port.log
-rw------- 1 root root 　4032000 2月 13 12:48 10.5.31.175-tty25-port.log
-rw------- 1 root root 　2382219 2月 13 13:23 10.5.31.175-tty5-port.log
#

All models of NS-2250 support the temperature sensor function.
You can acquire the temperature of inside NS-2250 using this sensor.
Also, it is possible to display the approximate outdoor temperature by specifying the certain correction value for adjustment.

For example, when the inside temperature of NS-2250 is 39 degrees and the outside temperature is 25 degrees, you can measure an approximate outside temperature if you set the correction to -14 degrees.
The correction value can be set within the range from -20 to 0 degrees.

To acquire the temperature information, the following ways are available.

・Executing "show environment" command by CLI
(c)NS-2250# show environment

[Environment status]

Power information
　 Power unit : AC
　 Power 1 : ON
　 Power 2 : OFF

Temperature information
　 Current temp : 39 deg C
　 Sensor : 39 deg C
　 Adjust : 0

・Getting MIB information via by SNMP manager.

In addition, NS-2250 is a low power consumption device which does not install the fan.
Since the temperature rise of the NS-2250 is rare, it does not support SNMP TRAP that notifies temperature abnormality, the function to detect temperature abnormality and automatically shut down.

You can install NS-2250 using CLI(Command Line Interface).
Since the values often used in the console server are registered as default, you can immediately use NS-2250 just by executing simple commands.

The sample settings are described in the Instruction Manual.
Please refer to "Chapter 4.8 Setting examples"of the Instruction Manual.

If you specify the serial ports as a list using hyphen "-" or comma ",", you can execute the multiple serial port settings with a single command.

（Example）
When setting the baud rate of the serial ports 1 to 32 to 19200bps.
set tty 1-32 baud 19200
When setting the baud rate of the serial ports 1 to 5 and 13 to 19200bps.
set tty 1-5,13 baud 19200　

You can upgrade and downgrade the version of the system software.
To upgrade please download the difference file from our website and execute it.
For the procedure of version upgrade, please refer to "readme" downloaded from the above website or "Chapter 5.5 Manage system software" of the Instruction Manual.
We don't upload the downgraded version file and the full image of system software to our website. Please contact us or the distributor where you bought this equipment.

NS-2250 has 4 status LED lamps with status 1-4.

During normal operation, all status lamps 1-4 are off.

When a hardware error occurs the status LED lamp 1-4 will light or blink.
If the status LED lamp 1-4 stays on or remains blinking the hardware may have any failure.

After accessing the console of NS-2250 and "MON>" is displayed, execute the err command and check the location of the failure.

Please refer to "Chapter 6.2.2 The STATUS lights are on or flashing" of the Instruction Manual for details.

The maximum number of Telnet/SSH sessions that can access NS-2250 is 5 sessions.
The maximum number of sessions that can access the equipment connected to the serial port is shown in the following table.
The maximum number of sessions that can access 1 serial port is 2 in normal mode sessions(rw) and 3 in monitor mode sessions(ro), totally 5 sessions.

　　　　　　　　 Telnet Only SSH Only
----------------------------------------------------
NS-2250-16　　　　80　　　 　　80
NS-2250-32　　　　96　　　 　　96
NS-2250-48　　　　96　　　 　　96

There are 2 ways to quit the session.
1.Quit the Telnet session itself by closing the window of Telnet session.
2.Enter the session suspension character code of port server menu.

In order to use the session suspension character code of port server menu you need to pre-register "set portd tty cmdchar" command.
Please refer to "Chapter 4.4.10 Configure other port server functions" of the Instruction Manual for details.

Please suspend the session by entering the session suspension character code of port server menu.
In order to use the session suspension character code of port server menu you need to pre-register "set portd tty cmdchar" command.
Please refer to "Chapter 4.4.10 Configure other port server functions" of the Instruction Manual for details.

The session status on the network side can be displayed by "show tcp" and "show udp" command.
While you are access the serial port of NS-2250 you can also display the session status by "show portd session" command.
To disconnect the sessions, execute "hangup" or "disconnect" command.

The setting of the serial port can be displayed by "show tty" command and the status of it can be displayed by "show stats tty" command.

(c)NS-2250# show tty
-------------------base----------------- -dsr-
tty　　 baud　bc　 parity st　flow　　　　dct
-----------------------------------------------------------
　1　　 9600　 8　 none　1 none　　　　off
　2　　 9600　 8　 none　1 none　　　　off
　3　　 9600　 8　 none　1 none　　　　off
　4　　 9600　 8　 none　1 none　　　　off
　5　　 9600　 8　 none　1 none　　　　off

(c)NS-2250# show stats tty
tty　 TX Octets　 RX Octets　 DSR　CTS　DTR　RTS　 CD
----------------------------------------------------------------------------
　1　　　　　0　　　 　 0　　off　　off　　on　　on　　off
　2　　　　　0　　　 　 0　　off　　off　　on　　on　　off
　3　　　　　0　　　 　 0　　off　　off　　on　　on　　off
　4　　　　　0　　　 　 0　　off　　off　　on　　on　　off
　5　　　　　0　　　 　 0　　off　　off　　on　　on　　off

You can eject the UBS memory except while reading/writing it(While STATUS LED4 lights) like during executing "write" command.

We are preparing the backup USB memory as an option.
Please order NS-993.

The password is stored in the startup file.
You can delete the password by initializing this startup file.

Concretely speaking, connect your terminal to the serial port of NS-2250 and start ROM monitor. Next, after loading the startp file which is not yet configured and start the system software then you can initialize the startup file.

Please refer to "Chapter 6.4.1 The password of the device management user has been forgotten" of the Instruction Manual for details.

In the port server menu, you can perform operations such as various operations of port logs, access to monitored equipment, and transmission of Break signals to monitored equipment.

1 display Port Log : Displaying the port log of the serial port from the top beginning.
2 display Port Log （LAST) : Displaying the latest port log of the serial port.
3 start tty connection : Switch the session of the serial port to the communication mode and accessing the monitored equipment.
4 close Telnet/SSH session : Quitting the Telnet/SSH session.
5 show all commands : Displaying all commands of this menu.
6 display & erase Port Log : Displaying the port log of the serial port and deleting them.
7 erase Port Log : Deleting the port log of the serial port.
8 send Port Log : Sending the port log of the serial port to the mail address and FTP server registered in advance.
9 show Port Log configuration : Displaying the setting of the port log of the serial port.
10 send break to tty : Sending the break character to the serial port.

The setting can be stored to the external server by ftp or tftp command of NS-2250 for backup.
Not only the backup but also the restoration (loading the setting) is possible.

Since NS-2250 does not support the control of the pasting speed such as the delay setting so please set your terminal so that an error does not occur.

For example, for Ver4.63 or later Teraterm, the setting procedure is as follows.
Setup -＞Additional settings -＞Copy and Paste -＞Paste delay per line

We have a security gateway server called "SmartGS".
Please contact us if you need details of SmartGS.