I have the following ip address "192.168.2.65"
Is there a way to convert the last 2 octets to 0.
I found the following, but it only lets me replace the last one, i need to replace the last 2.
ip = 192.168.2.65
output='.'.join(ip.split('.')[:-1]+["0"])
print(output)
which gives me 192.168.2.0 and i would like to be 192.168.0.0
Index -1 means the last index. If you want to change two, change your index to -2.
output='.'.join(ip.split('.')[:-2]+["0", "0"])
You could also use a regex based approach here:
ip = "192.168.2.65"
output = re.sub(r'\.\d+\.\d+$', '.0.0', ip)
print(output) # prints 192.168.0.0
Dependant on the logic you are trying to apply.. if you are simply wanting to modify a string, the other answers are correct.
However, if you are looking to get the network address for the subnet an address resides in, you should handle the addresses correctly and use the ipaddress module.
This will assist in calculating the correct network & broadcast addresses, and allow you to check inclusions in networks etc.
import ipaddress
interface = IPv4Interface('192.168.2.35/255.255.0.0')
print(interface.network)
#192.168.0.0/16
print(interface.network.network_address)
#192.168.0.0
print(interface.network.broadcast_address)
#192.168.255.255
Related
I'm kind of stuck on a particular issue. I need to calculate the subnets an IP address belongs to. It could be done in SQL or Python or similar.
So if I have e.g. 100.100.100.105 I need to get all the subnets:
100.100.100.105/32
100.100.100.104/31
100.100.100.104/30
100.100.100.104/29
100.100.100.96/28
100.100.100.96/27
100.100.100.64/26
...
100.64.0.0/10
100.0.0.0/9
...
64.0.0.0/2
0.0.0.0/1
But really don't know how to approach the issue.
you can achieve this with the python3 built in ipaddress module
import ipaddress
addresses = []
# get the int representation of your ip
ip = int(ipaddress.IPv4Address('100.100.100.105'))
for mask in range(32):
addresses.append(f'{ipaddress.IPv4Address(ip & ((2**32-1)-(2**mask -1)))}/{32-mask }')
At each iteration, we apply the mask to our IP by doing a logic AND operation between the integer representations of the IP and the mask. We then convert the result to ip octets and append the '/24' subnet notation. You can replace 2**32-1 with 4294967295, I left it there so its clearer what is happening.
I have an IP address that I need to split in order to know the location of the device.
s = "11.19.27.55"
ip = [item[::-1] for item in s[::-1].split('.', 1)][::-1]
print(ip)
Result:
['11.19.27', '55']
How can I now compare to certain parts of this result?
The first part I need for location second part for knowing which device it is.
I found the solution myself:
print(ip[0]) for the first part
print(ip[1]) for the second part
Providing that I have this list which contains a number IP addresses:
IpAddresses = ["192.168.0.1","192.168.0.2","192.168.0.3","192.168.0.4"]
Then after receiving a packet I want to check if its source address is included in the predefined list IpAddresses
data, address = rxsocket.recvfrom(4096)
I have tried two alternatives, but both didn't work:
First:
if (address in IpAddresses):
do something
Then, I tried to convert address into string before making the comparison:
str_address = str(address)
if (str_address in IpAddresses):
do something
I am not familiar with python syntax, so please could you show me how to do this.
if address[0] in IpAddresses:
since the address object appears as a tuple only the 0th index appears in your list so you should check for its existence (also you can usually skip the parenthesis on an if statement unless it makes the if statement less readable)
I am questioning the results of the ipcalc module (ipcalc) for Python (it seems that netaddr may be a better choice).
Let's take 192.168.1.25/30 as an example. In binary, the last octet is 00011001 AND 11111100 = 00011000, so I get 192.168.1.24 as the Network ID and the range 192.168.1.24 - 192.168.1.27.
Using ipcalc, when I specify
subnet = ipcalc.Network('192.168.1.25/30')
for x in subnet: print x
The output is
192.168.1.25
192.168.1.26
192.168.1.27
192.168.1.28
I am not understanding the inconsistency. When using CIDR notation, it seems that specifying both 192.168.1.24/30 and 192.168.1.25/30 (or .26/30 or .27/30) refer to the same subnet.
Is that correct? Is this just a bug in the ipcalc module?
There is an open bug for this at the moment: No way to resolve IP + Netmask to Network Object
And an earlier bug report that discuss the matter: Strange subnet calculations
But they have also added a function called network to get the network address from an IP. From the manual:
>>> localnet = Network('127.128.99.3/8')
>>> print localnet.network()
127.0.0.0
The manual specifically says that the constructor Network should take a network address as its first argument, not any IP in the network. Rather confusing if you ask me (especially since the above code block breaks that condition). I would at least read the code for the module before using it.
It's correct the subnet is 192.168.1.24/30 so the ips 192.168.1.24 to 192.168.1.27 make part of this network.
Given the range xxx.xxx.xxx.(195-223)
Is that correct to write it in xxx.xxx.xxx.196/29 and check whether an IP is in the given network by doing
from ipaddr import IP, CIDR
#if IP('xxx.xxx.xxx.xxx') in IP('xxx.xxx.xxx.196/29') or
#if IP('xxx.xxx.xxx.xxx') in CIDR('xxx.xxx.xxx.196/29')
I didn't see IP in ipaddr, only IPAddress.
May be like this?
from ipaddr import IPAdddress, IPNetwork
if IPAddress('10.0.0.195') in IPNetwork('10.0.0.196/29'):
pass
I haven't used the ipaddr module, but note that /29 means that your network mask is 255.255.255.248 and that you only have the latest 3 bits to address 2^3 = 8 different hosts in your network ranging from xxx.xxx.xxx.248 to xxx.xxx.xxx.255. That's outside of the range you want to check.
For more information, please have a look at the subnetwork wikipedia page.