Configuring tftpd in linux is really a pain in my neck…lol…
Thanks Andrey for helping me to rectify the problem remotely.
The main problem with my linux configuration was the credential denied my router from executing commands to linux tftpd.
Understanding chmod
change mode is the command that change the rights of user, group and/or other.
The binary is like a three buttoned dip switch:
Execute = 001 = 1 in decimal
write = 010 = 2 in decimal
read = 100 = 4 in decimal
The combinations:
no write, no read and no execute = 000 = 0
read, no write and no execute = 100 = 4
read, write and no execute = 100 + 010 + 000 = 110 = 6
read, write and execute = 100 + 010 + 001 = 111 = 7
no read, no write, execute = 001 = 1
no read, write and execute = 000 + 010 + 001 = 011 = 3
read, no write and execute = 100 + 000 + 001 = 101 = 5
chmod options
Based on the combinations above, interpret the meaning of chmod options
where r = read, w = write and x = execute files and/or search directories
Example 1: chmod 755
Means: User rwx, group and other rx
[root@cyruslab /]# ls -l /usr/sbin/in.tftpd
-rwxr-xr-x 1 root root 32688 Jan 3 23:01 /usr/sbin/in.tftpd
Example 2: chmod 777
Means: user, group and other rwx
Example 3: chmod 666
Means: user, group and other rw
chmod option representation
Example: chmod 777
chmod user group other
Modify tftp configuration
For server_args I have changed to server_args = -s /tftpboot, I have made a directory in root “/” using mkdir /tftpboot. Note in this configuration file the user is root. After the configuration was saved, restart the service:
service xinetd restart
tftp depends on xinetd, however tftp can run as standalone.
Verify the service by using:
[root@cyruslab ~]# chkconfig –list tftp
tftp on
From the Linux window, go to System > Administration > Firewall, turn on the tftp as shown in this screenshot.
Make tftp ready to be used by external host
[root@cyruslab ~]# touch /tftpboot
[root@cyruslab ~]# chmod 777 /tftpboot
Cisco router is not a root user, it belongs to other category which is the last digit, so these combinations can be used:
1. chmod 757 /tftpboot
2. chmod 707 /tftpboot
Test with router
2651-1#copy run tftp
Address or name of remote host []? 192.168.1.107
Destination filename [2651-1-confg]?
!!
2103 bytes copied in 2.275 secs (924 bytes/sec)
[root@cyruslab ~]# cd /tftpboot
[root@cyruslab tftpboot]# ls
2651-1-confg cisco
[root@cyruslab tftpboot]#
cyruslab 