Skip to main content

System History and the undo command

By
The history of system configuration changes is held until the next router shutdown. The invoked commands can be 'undone' using the /undo command. By invoking the command several times, the configuration changes can be 'undone' in reverse order they have been invoked. Use the /system history print command to see the list of performed actions:




[MikroTik] system history> print
Flags: U - undoable, R - redoable, F - floating-undo 
  ACTION                                   BY            POLICY          
U nat rule changed                         admin         write           
U nat rule changed                         admin         write  
[MikroTik] system history>


The list is printed with the newest actions at the top. Thus, in this example, the /undo command would 'undo' the changed nat rule from the top:




[MikroTik] system history> /undo
[MikroTik] system history> print


 Flags: U - undoable, R - redoable, F - floating-undo 
  ACTION                                   BY            POLICY               
U nat rule changed                         admin         write  
[MikroTik] system history>


Tip: If you accidentally removed some item, or set wrong argument value, just execute the /undo command to undo previously done action. The /redo would do the opposite - redo the previous undo action.
Labels:

Comments

Post a Comment

Popular posts from this blog

DHCP option 121

By
http://tools.ietf.org/html/rfc3442 This is used to add a classless  static route to the DHCP clients. To add option 121 to a Mikrotik DHCP server, it's value is specified in HEX. The format is as follows. 0xnnddddddddgggggggg where n=mask, d=destination, g=gateway. To convert ip address to HEX, you convert each octet, so 192=C0, 168=A8, 55=37, 1=01 You can use a tool such as  http://www.miniwebtool.com/ip-address-to-hex-converter/?ip=192.168.55.1 Example: To add a route to the destination network of 192.168.55.0/24 via gateway 172.16.10.1. /ip dhcp-server option add name=classlessroutes code=121 value=0x18C0A837AC100A01 where 18 is 24 in hex. *note: depending on the subnet mask, you may only need to specify 0-4 octets. In fact only the non-zero, or network portion of the subnet. Here is a table from the RFC. subnet mask Number of octets 0 0 1- 8 1
Post a Comment
Read more

Mikrotik Bridge Horizon

By
To achieve similar functionality to Cisco's private VLANS, where all ports are on the same L2 segment, but cannot exchange packets, you can use Mikrotik's Bridge Horizon feature. Basically, every port in a bridge is assigned a horizon value, and RouterOS will only forward frames to other interfaces in the bridge that have different horizon values. This means that you assign the same horizon value to the interfaces that you don't want to be able to communicate. For example, you want to bridge all your customers and use a single /24 subnet and the same gateway. Typically this is bad and poses a huge security risk, not to mention performance issues. If you assign the same horizon value to the customer interfaces, then the router will not forward traffic between customers. Customer A will not be able to ping Customer B. If you had a server, such as an IP-PBX that all customers needed to access, and you were lazy and added it to the bridge, then you would assign a diff
Post a Comment
Read more

Mikrotik mac address filtering

By
Playing with an RB493G and wanted to allow only a certain list of mac addresses to be able to connect. We all know this type of security is in no way fool proof. The 493G has 2 switch chips in it and ports 2-5 are on switch2 and ports 1 and 6-9 are on switch1 Much like /ip firewall filter rules, switch rules are checked chronologically (top down). And like /ip firewall filter rules, you must specify a deny rule. Although there is no 'deny' rule as such, you can just specify a redirect to null (specify no port) which achieves the same result.
Post a Comment
Read more