Re: slow tcp with isdn

Gerd Knorr (
Tue, 29 Jul 1997 12:42:22 +0200

>> Can they get lost *after* tcpdump has
>> seen them? Becauce of a bad checksum or something? How to check this?
>Checksum. Look at the kernel syslog and/or /proc/net/snmp.

Syslog says nothing. ifconfig ippp0 says 0 rx/tx errors, so does
/proc/net/snmp for ip. But ip checksum is the ip header only, right?

I grep'ed net/ipv4/tcp*.c for a bad-checksum-printk(), but hav'nt found
one. Does the 2.0.30 kernel log and/or count bad tcp packets? If not,
is there any way to do this?

/proc/net/snmp has no somethingError entry for tcp. But there is a
RetransSegs entry. This one lists 5. Hmm...
Is this incoming? outgoing? both?