syn flood?

[Marek Hevier]

Zdravim znovu celu konferu....
mam tu problem, s ktorym neviem zatial pohnut...
Na server jednoducho neprichadza posta, a odchodziu server posle, iba 
z jednej domeny ju vracia.
Mam RH71 a pouzivam sendmail.
vypis logov pre onu spominanu domenu:

Nov  5 20:27:25 uhra sendmail[22497]: hA4MiIa15795: 
to=<vjanco na post.sk>, ctladdr=<vladus na uhra.mtf.stuba.sk> (518/45), 
delay=20:43:07, xdelay=00:00:01, mailer=esmtp, pri=103531122, 
relay=smtp.post.sk. [217.67.20.134], dsn=4.0.0, stat=Deferred: 
Connection refused by smtp.post.sk.

Mam podozrenie ze to moze suvisiet nejak s DOS utokom, pretoze po 
netstatnuti dostanem nasledovny vysledok:

tcp        0      0 0.0.0.0:22              0.0.0.0:*               
LISTEN
tcp        0      0 0.0.0.0:25              0.0.0.0:*               
LISTEN
tcp        0      0 147.175.139.10:25       12.129.205.51:11557     
SYN_RECV
tcp        0      0 147.175.139.10:25       62.168.28.239:4859      
SYN_RECV
tcp        0      0 147.175.139.10:25       12.129.205.60:19703     
SYN_RECV
tcp        0      0 147.175.139.10:25       62.168.28.239:4860      
SYN_RECV
tcp        0      0 147.175.139.10:25       64.156.187.151:51089    
SYN_RECV
tcp        0      0 147.175.139.10:25       12.129.205.67:25883     
SYN_RECV
tcp        0      0 147.175.139.10:25       12.129.205.45:38839     
SYN_RECV
tcp        0      0 147.175.139.10:25       12.129.205.69:49654     
SYN_RECV
tcp        0      0 147.175.139.10:25       12.129.205.58:8259      
SYN_RECV
tcp        0      0 147.175.139.10:25       212.5.216.21:46416      
SYN_RECV

zapis v /etc/hosts.allow

sendmail: all EXCEPT PARANOID

vie mi niekto pomoct? vopred dakujem
Marek




------------------------------------------------
Careful what you wish
careful what you say
you may regret it...
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