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AWK to get details from /proc/net/tcp and /proc/net/udp when netstat and lsof are not available
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# Gawk version | |
# Remote | |
grep -v "rem_address" /proc/net/tcp | awk '{x=strtonum("0x"substr($3,index($3,":")-2,2)); for (i=5; i>0; i-=2) x = x"."strtonum("0x"substr($3,i,2))}{print x":"strtonum("0x"substr($3,index($3,":")+1,4))}' | |
# Local | |
grep -v "rem_address" /proc/net/tcp | awk '{x=strtonum("0x"substr($2,index($2,":")-2,2)); for (i=5; i>0; i-=2) x = x"."strtonum("0x"substr($2,i,2))}{print x":"strtonum("0x"substr($2,index($2,":")+1,4))}' | |
# No Gawk | |
# Local | |
grep -v "rem_address" /proc/net/tcp | awk 'function hextodec(str,ret,n,i,k,c){ | |
ret = 0 | |
n = length(str) | |
for (i = 1; i <= n; i++) { | |
c = tolower(substr(str, i, 1)) | |
k = index("123456789abcdef", c) | |
ret = ret * 16 + k | |
} | |
return ret | |
} {x=hextodec(substr($2,index($2,":")-2,2)); for (i=5; i>0; i-=2) x = x"."hextodec(substr($2,i,2))}{print x":"hextodec(substr($2,index($2,":")+1,4))}' | |
# Remote | |
grep -v "rem_address" /proc/net/tcp | awk 'function hextodec(str,ret,n,i,k,c){ | |
ret = 0 | |
n = length(str) | |
for (i = 1; i <= n; i++) { | |
c = tolower(substr(str, i, 1)) | |
k = index("123456789abcdef", c) | |
ret = ret * 16 + k | |
} | |
return ret | |
} {x=hextodec(substr($3,index($3,":")-2,2)); for (i=5; i>0; i-=2) x = x"."hextodec(substr($3,i,2))}{print x":"hextodec(substr($3,index($3,":")+1,4))}' | |
# All in one | |
awk 'function hextodec(str,ret,n,i,k,c){ | |
ret = 0 | |
n = length(str) | |
for (i = 1; i <= n; i++) { | |
c = tolower(substr(str, i, 1)) | |
k = index("123456789abcdef", c) | |
ret = ret * 16 + k | |
} | |
return ret | |
} | |
function getIP(str,ret){ | |
ret=hextodec(substr(str,index(str,":")-2,2)); | |
for (i=5; i>0; i-=2) { | |
ret = ret"."hextodec(substr(str,i,2)) | |
} | |
ret = ret":"hextodec(substr(str,index(str,":")+1,4)) | |
return ret | |
} | |
NR > 1 {{if(NR==2)print "Local - Remote";local=getIP($2);remote=getIP($3)}{print local" - "remote}}' /proc/net/tcp |
Thank you so much, I really appreciate you sharing these scripts
Thank you so much my friend, i was gonna bang my head into the wall for couple of weeks at least.... Its bad when you need to check network connections in a container without ss or netstat....
kubectl describe pod/xxxx,docker inspect xxxxxxxxxxxxx .
👍
very nice!
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