Solved: How to stop on-going IOS tftp transfer?

sirajmuneer · ‎08-11-2009

Team,

are there any IOS commands that can be used to stop/kill/halt IOS image transfer via TFTP ?

thanks

Edison Ortiz · ‎08-11-2009

If you are telneting to that device via the port you are planning to shut down, you need to be careful thus I understand your concern :)

If the key combination isn't working as suggested, you can apply an ACL to the interface facing the TFTP server.

ip access-list extended KILL-TFTP

deny udp any eq 69 any

permit ip any any

interface xxx

ip access-group KILL-TFTP in

HTH,

__

Edison.

View solution in original post

Jerry Ye · ‎08-11-2009

Have you tried Ctrl-^ ( = Ctrl Shift 6).

HTH,

jerry

jez · ‎01-28-2021

this works for me. great.

mnandira@cisco.com · ‎06-10-2022

thanks ... ctrl shift 6 works like a charm

Lucien Avramov · ‎08-11-2009

IF you are already telnetting in during the transfer and see the transfer on the screen, use CTRL+SHIFT+6+X (= CTRL^X)

If you are not seing the transfer and it happens on someone else's Telnet window, then you can telnet to the router and flap the interface with shut/ no shut to kill it

sirajmuneer · ‎08-11-2009

i did tried ctrl+z and CTRL+SHIFT+6+X few times, with no luck.

is there any other way other than shut/no shut the port?

thanks

Jerry Ye · ‎08-11-2009

How about killing the TFTP server daemon?

Regards,

jerry

sirajmuneer · ‎08-11-2009

i do have tftp server access and it is a UNIX box. not sure how to kill tftp job using UNIX command and of course it is out of this forum's scope.

Jerry Ye · ‎08-12-2009

You can edit the file /etc/inetd.conf or /etc/inet/inetd.conf, and comment out the following line like this

#tftp dgram udp wait root /usr/sbin/tcpd in.tftpd

Then restart the inetd like this

pkill -HUP inetd

HTH,

jerry

Lucien Avramov · ‎08-11-2009

telnet to the router from another window and bounce the link, if you dont have access to the TFTP server itself.

Edison Ortiz · ‎08-11-2009

If you are telneting to that device via the port you are planning to shut down, you need to be careful thus I understand your concern :)

If the key combination isn't working as suggested, you can apply an ACL to the interface facing the TFTP server.

ip access-list extended KILL-TFTP

deny udp any eq 69 any

permit ip any any

interface xxx

ip access-group KILL-TFTP in

HTH,

__

Edison.

chinkevi_2 · ‎08-11-2009

i personally find most pc does not work with Ctrl-^X or Ctrl-z.. i often use Ctrl-6 and it works.