OVERRUN ERRORS with SLIP

OVERRUN ERRORS with SLIP

Post by Matt Prest » Thu, 17 Nov 1994 04:10:24



I was wondering if OVERRUN ERRORS are normal when using slip.  I have a
14.4k modem with V.32 v.42 MNP etc etc.  I seem to get quite a number of
them.  To connect to my SLIP provider I use all the compression methods
as well as RTS/CTS Flow Control.  I am also using a 16550 serial card
from BOCA.  Perhaps I'm looking in the wrong direction.  Someone
recommended I lower my MTU's but I have not tried that.  Below is my
ifconfig with the errors displayed:

sl0       Link encap Serial Line IP  
          inet addr 192.67.245.42  P-t-P 192.67.245.1  Mask 255.255.255.0
          UP POINTOPOINT RUNNING  MTU 1500  Metric 1
          RX packets 1233379 errors 1 dropped 0 overrun 709
          TX packets 1513719 errors 0 dropped 1388 overrun 869

This is only in about 30 mins worth of SLIP use.
I've tried other modems with it and other serial ports as well as new
cables and still the same problem.  
Thanks for any help

 
 
 

OVERRUN ERRORS with SLIP

Post by jle.. » Thu, 17 Nov 1994 12:43:10



>I was wondering if OVERRUN ERRORS are normal when using slip.  I have a
>14.4k modem with V.32 v.42 MNP etc etc.  I seem to get quite a number of
>them.  To connect to my SLIP provider I use all the compression methods
>as well as RTS/CTS Flow Control.  I am also using a 16550 serial card
>from BOCA.  Perhaps I'm looking in the wrong direction.  Someone
>recommended I lower my MTU's but I have not tried that.  Below is my
>ifconfig with the errors displayed:
>sl0       Link encap Serial Line IP  
>          inet addr 192.67.245.42  P-t-P 192.67.245.1  Mask 255.255.255.0
>          UP POINTOPOINT RUNNING  MTU 1500  Metric 1
>          RX packets 1233379 errors 1 dropped 0 overrun 709
>          TX packets 1513719 errors 0 dropped 1388 overrun 869
>This is only in about 30 mins worth of SLIP use.

That's an incredible number of packets transfered for 30 minutes.  Are you
sure these nubmers are from only 30 minutes into a session?  Those numbers are
similar to our departmental email server's eth0 interface after 6 days of
running.

Are you sure you have a 16550A UART for the modem?  I run Linux on a 386sx-20
with the port at 115200bps for a v.FC modem and don't get overruns on the
server.  I do get occasional overruns on my  486-33 PPP client running WFWG
3.11.

------------------------------------------------------------------

                               |          OR

 Mime attachments are OK       |          
 But please ask before sending unsolicited huge files.        

http://inorganic5.chem.ufl.edu [temporarily down :-( ]


 
 
 

OVERRUN ERRORS with SLIP

Post by Adrian (Sha » Thu, 17 Nov 1994 21:57:32


|> I was wondering if OVERRUN ERRORS are normal when using slip.  I have a
|> 14.4k modem with V.32 v.42 MNP etc etc.  I seem to get quite a number of
|> them.  To connect to my SLIP provider I use all the compression methods
|> as well as RTS/CTS Flow Control.  I am also using a 16550 serial card
|> from BOCA.  Perhaps I'm looking in the wrong direction.  Someone
|> recommended I lower my MTU's but I have not tried that.  Below is my
|> ifconfig with the errors displayed:
|>
|> sl0       Link encap Serial Line IP  
|>           inet addr 192.67.245.42  P-t-P 192.67.245.1  Mask 255.255.255.0
|>           UP POINTOPOINT RUNNING  MTU 1500  Metric 1
|>           RX packets 1233379 errors 1 dropped 0 overrun 709
|>           TX packets 1513719 errors 0 dropped 1388 overrun 869
|>
|> This is only in about 30 mins worth of SLIP use.
|> I've tried other modems with it and other serial ports as well as new
|> cables and still the same problem.  
|> Thanks for any help
|>

I've got a similar story. The following is an ifconfig after an ftp (100K or so)
and a telnet session took place at the same time;

sl0       Link encap Serial Line IP  
          inet addr 128.141.200.203  P-t-P 128.141.200.201  Mask 255.255.0.0
          UP POINTOPOINT RUNNING  MTU 296  Metric 1
          RX packets 3041 errors 0 dropped 0 overrun 2727
          TX packets 3826 errors 0 dropped 87 overrun 3567

I'm running an old slackware distribution with kernel 1.0.8 and SLIP
version 0.7.5.

I'm about to upgrade to slackware 2.1. Will this help?

Cheers,

Adrian Mills

 
 
 

OVERRUN ERRORS with SLIP

Post by Uri Blumenth » Fri, 18 Nov 1994 06:21:45


DARN! It ought to be in the HOWTO or README...

Those are NOT overruns: those are compressed
headers, which "ifconfig" mistakes for
overruns.
--
Regards,

------------
<Disclaimer>

 
 
 

OVERRUN ERRORS with SLIP

Post by Niku Toivo » Sat, 19 Nov 1994 07:49:36


: I was wondering if OVERRUN ERRORS are normal when using slip.  I have a
: 14.4k modem with V.32 v.42 MNP etc etc.  I seem to get quite a number of
: them.  To connect to my SLIP provider I use all the compression methods
: as well as RTS/CTS Flow Control.  I am also using a 16550 serial card
: from BOCA.  Perhaps I'm looking in the wrong direction.  Someone
: recommended I lower my MTU's but I have not tried that.  Below is my
: ifconfig with the errors displayed:

: sl0       Link encap Serial Line IP  
:           inet addr 192.67.245.42  P-t-P 192.67.245.1  Mask 255.255.255.0
:           UP POINTOPOINT RUNNING  MTU 1500  Metric 1
:           RX packets 1233379 errors 1 dropped 0 overrun 709
:           TX packets 1513719 errors 0 dropped 1388 overrun 869

: This is only in about 30 mins worth of SLIP use.
: I've tried other modems with it and other serial ports as well as new
: cables and still the same problem.  
: Thanks for any help

For a long time I was wondering the same. Then some time ago I
upgraded my netutils, along with them ifconfig. Now it says this:

sl0       Link encap:VJ Serial Line IP  
          inet addr:130.233.211.4  P-t-P:130.233.211.253  Mask:255.255.0.0
          UP POINTOPOINT RUNNING  MTU:512  Metric:1
          RX packets:22132 errors:0 dropped:0 compressed:21059
          TX packets:23724 errors:0 dropped:0 compressed:21635

So, it seems that the old ifconfig reported compressed (CSLIP) packets
as overrun errors...

--
---
 Niku 'SSwift' Toivola             "I have just one question. If Christians

 http://closenet.hut.fi/~sswift/   there for?"           -- Wish I knew who

 
 
 

OVERRUN ERRORS with SLIP

Post by A hippie ge » Sun, 20 Nov 1994 00:17:31




>DARN! It ought to be in the HOWTO or README...

>Those are NOT overruns: those are compressed
>headers, which "ifconfig" mistakes for
>overruns.
>--
>Regards,


I think I will have to point out this here:

Twilight_Zone is local (home)

Twilight_Zone:/# netstat -i
Kernel Interface table
Iface   MTU Met  RX-OK RX-ERR RX-DRP RX-OVR  TX-OK TX-ERR TX-DRP TX-OVR
Flags
lo     2000   0      0      0      0      0     35      0      0      0 BLRU
sl0    1500   0 206235      0      0 193291 211410      0     25 197147 BRU

and leary is remote (on the net):

leary:~$ /sbin/netstat -i
Kernel Interface table
Iface   MTU Met  RX-OK RX-ERR RX-DRP RX-OVR  TX-OK TX-ERR TX-DRP TX-OVR
Flags
lo     2000   0      0      0      0      0  12528      0      0      0 BLRU
ppp0   1500   0   1042      0      0      0   1010      0      0      0 PRU
sl0    1500   0 544022      0      0 197247 529996      0     94 193435 NRU
eth0   1500   0 9225412      0      0      0 9169292      0      0      0
BRU

This is after being up for a week.

I also notice that if I ftp large files, (over 800k) more then once in a row
(doing 2 or 3 large files, one right after another), the link will drop.
Yes, ctsrts is enabled on both ends, and I am using USR 28.8k modems with
16550's on the port with full cables.

Anyone have any ideas?
--
Another Happy Hippie on cosmic.com (My views are my own, not cosmic.com's)
telnet to wow.cosmic.com username guest to register for an account.

Dial 516-342-7270 (14.4k USRobotics Modems) for dial-up access.

 
 
 

OVERRUN ERRORS with SLIP

Post by Andreas Haum » Mon, 21 Nov 1994 09:28:29


Hi!

Quote:> Those are NOT overruns: those are compressed
> headers, which "ifconfig" mistakes for
> overruns.

Newer versions of "ifconfig" already know the difference. Just upgrade
and you will get the correct text.

- andreas
--

----------------------+-------------------------------+------------------------
andreas haumer        | phone: +43.1.6001508          |
buchengasse 67/8      | fax:   +43.1.6001084          |
a-1100 vienna         | e-mail:                       | god is real -

 
 
 

1. Overrun Error with SLIP

Anyone know what's the deal with overrun errors? I've never had
them before. But lately I've had tons on my SLIP connection.
I have 2 ports both are 16550AFN's and I've setserial them to
spd_hi, and don't seem to have problems with dialups/dialouts
at least as far as I can tell, but just now I fired up the slip link
and ftp'd to sunsite and did an ls -lR, this is what I got:

sl0       Link encap Serial Line IP
          inet addr 198.163.154.24  P-t-P 130.179.16.143  Mask 255.255.255.0
          UP POINTOPOINT RUNNING  MTU 1500  Metric 1
          RX packets 462 errors 0 dropped 0 overrun 404
          TX packets 478 errors 0 dropped 0 overrun 353

Thats almost an overrun for every packet! Geez.

Someone please clarify the norm for me.

--
--------------------------------------------------------------------------



2. PPP: LCP Timeout

3. Slip - Errors and Overruns

4. mSQL database package

5. Slip Overruns

6. Slow printing

7. Meaning of RX/TX packet overruns in SLIP?

8. Eiffel link errors on Linux...

9. SLIP Serial packet *overruns*

10. SLIP: overruns and >38400 baud?

11. SLIP overruns and LYNX

12. Serious *overrun* problems with SLIP

13. Overruns with SLIP