Hi folks.
I'd like to get some feedback on a hugely updated /etc/services i've done today.
It basically merges the old /etc/services with almost all current official IANA services.
I've tried to make sure the file is sane and in order, but due to the huge amount of new services i'd like to give it some selected exposure and feedback before i think about putting it into our setup package.
The file can be downloaded from here:
http://people.redhat.com/pknirsch/services
Just dump it as a replacement in /etc (maybe making a copy of the old /etc/services first, but shouldn't be necessary as the first part of the file is identical to our old one).
I'd especially like to get some feedback from people using it on network servers or monitoring machines where apps like nmap, tcpdump and ethereral are run. My main interest is if any errors pop up and if anyone gets performance problems (because for worst case scenarios it can now take up to 15 times as long for getservbyname() to complete).
Thanks in advance,
Read ya, Phil
On Tuesday 24 January 2006 13:54, Phil Knirsch wrote:
http://people.redhat.com/pknirsch/services
Just dump it as a replacement in /etc (maybe making a copy of the old /etc/services first, but shouldn't be necessary as the first part of the file is identical to our old one).
I'd especially like to get some feedback from people using it on network servers or monitoring machines where apps like nmap, tcpdump and ethereral are run. My main interest is if any errors pop up and if anyone gets performance problems (because for worst case scenarios it can now take up to 15 times as long for getservbyname() to complete).
Thanks in advance,
Phil,
I just ran an nmap of my network with the new file in /etc/services i scanned a /24 subnet with 110 hosts in 310 seconds
a scan from october last year took 111 seconds with 105 hosts
i didint notice any errors in the scan
Dennis
Phil Knirsch wrote:
Hi folks.
I'd like to get some feedback on a hugely updated /etc/services i've done today.
It basically merges the old /etc/services with almost all current official IANA services.
I've tried to make sure the file is sane and in order, but due to the huge amount of new services i'd like to give it some selected exposure and feedback before i think about putting it into our setup package.
The file can be downloaded from here:
http://people.redhat.com/pknirsch/services
Just dump it as a replacement in /etc (maybe making a copy of the old /etc/services first, but shouldn't be necessary as the first part of the file is identical to our old one).
I'd especially like to get some feedback from people using it on network servers or monitoring machines where apps like nmap, tcpdump and ethereral are run. My main interest is if any errors pop up and if anyone gets performance problems (because for worst case scenarios it can now take up to 15 times as long for getservbyname() to complete).
Thanks in advance,
Read ya, Phil
I'd really suggest instead making a poll of what people would find useful.
There are going to be a lot of things in there that will probably never be useful, e.g. 2545 "sis-emt" is one I registered, and I'm pretty sure is now unused, or certainly of only very limited use.
Just a thought.
Bill Crawford wrote:
I'd really suggest instead making a poll of what people would find useful.
There are going to be a lot of things in there that will probably never be useful, e.g. 2545 "sis-emt" is one I registered, and I'm pretty sure is now unused, or certainly of only very limited use.
Just a thought.
Whats the harm in having them there though?
Rahul Sundaram wrote:
Bill Crawford wrote:
I'd really suggest instead making a poll of what people would find useful.
There are going to be a lot of things in there that will probably never be useful, e.g. 2545 "sis-emt" is one I registered, and I'm pretty sure is now unused, or certainly of only very limited use.
Just a thought.
Whats the harm in having them there though?
Wasted time, mostly. I know we're talking about less than a second per, but it's still unnecessary.
Harm would mostly be e.g. confusion caused to people looking at netstat output, though I'm pleased to see things like the AOL port numbers listed there (which is certainly common enough that I see it primarily useful; however even then .. *shrug*).
Anyway, it's wasted time for an app to search. Granted I'm only referring to one particular entry, but I can guarantee that for the majority of people out there, if a connection happens to be on port 2545, having it show up as "sis-emt" isn't helping them one bit :)
Same probably goes for a lot of the others, is the point I was making. If that ends up being a majority of them (which I suspect) it really is just wasted time. Trivial in many cases, yes, but still quite unnecessary, and again, probably confusing more than helpful anyway. In other words:-
Cost: time. Benefit: loss of time figuring out why a connection shows up as "foo" in netstat output.
(i.e. the "benefit" side is negative too.)
FWIW I do agree that having a few more than the barest minimum is probably useful. But multiplying up the time taken to scan /etc/services significantly for no or possibly negative benefit is just (IMO) poor engineering choice.
Again, I'm explicitly talking about a subset of what's there, not saying "don't expand it, DANGER WILL ROBINSON DANGER" without thought. I *know* at least one entry in there is pretty useless. And I'm sure there will be others.
I'm asking for a positive input of what folk feel *should* be in there, and suggesting that all such be included. Hoping it'll be less than the full list :)
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Bill Crawford -
Dennis Gilmore -
Phil Knirsch -
Rahul Sundaram