new kernel can not access www.sun.com

[K.C. Chan]

I've just upgraded to kernel version 2.4.17 and I can't access www.sun.com where as I can access www.yahoo.com and this forums. But when booting up with previous kernle 2.4.3-12, it works perfectly. Could some suggest on how should I pinpoint where the problem is comming from and how to fix it? BTW, there's I am not gingo through any proxy or firewalls. Thanks.

[Stuart Browne]

Whilst booted up in 2.4.17, try 'dig www.sun.com'.

It should come up with something like the following:

; <<>> DiG 9.1.3 <<>> www.sun.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3994
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 6, ADDITIONAL: 6

;; QUESTION SECTION:
;www.sun.com. IN A

;; ANSWER SECTION:
www.sun.com. 66294 IN A 192.18.97.241

;; AUTHORITY SECTION:
sun.com. 63459 IN NS ns-os.sun.com.
sun.com. 63459 IN NS ns-brm.sun.com.
sun.com. 63459 IN NS ns.usec.sun.com.
sun.com. 63459 IN NS ns1.eu.sun.com.
sun.com. 63459 IN NS ns1.pr.sun.com.
sun.com. 63459 IN NS ns.sun.com.

;; ADDITIONAL SECTION:
ns-os.sun.com. 17029 IN A 192.9.9.6
ns-brm.sun.com. 16034 IN A 192.18.99.5
ns.usec.sun.com. 8782 IN A 192.9.48.3
ns1.eu.sun.com. 11379 IN A 192.18.240.8
ns1.pr.sun.com. 34525 IN A 192.18.16.2
ns.sun.com. 19968 IN A 192.9.9.3

;; Query time: 56 msec
;; SERVER: 192.231.136.2#53(192.231.136.2)
;; WHEN: Mon Feb 25 23:27:03 2002
;; MSG SIZE rcvd: 263

If that comes up ok, it's time to start checking routing tables. ie:

traceroute -n 192.18.97.241

see where that leads you. It should tell you whether there is a problem getting out of your network, or whether it's somewhere further upstream.

[K.C. Chan]

Stuart I've tried all that before posting, The result is inconclusive bec. I got the same result with kernel 2.4.3-12 vs. kernel 2.4.17. I've tested this on another box, load up kernel 2.4.17 and try access www.sun.com via lynx, konqueror, netscape, and mozilla. No luck. However when I boot both machine with kernel 2.4.3-12 (prior kernel version), everything is cool. So I think either I'm missing a certain module(s) or their is a serious bug with kernel 2.4.17. Have any one run into this problem with kernel 2.4.17? Thanks.

[Ron Kinner]

I don't think you have a DNS or routing problem.

ping sun.com

works doesn't it?

The problem probably has somethingto do with some code on the www.sun.com webpage. Maybe some Java Applet which your new kernel can't handle. (What makes the arrow move in the Get the new Java Plug-in for XP add?).

Do you get an error message when you try to go to the site or does it try to load and stay blank or what?

Ron

[K.C. Chan]

Ron, your're assumption is correct; I do not have a DNS or routing issues. I am able to ping www.sun.com. But when I tried to access www.sun.com via browser, it returns erro: "operation time out" on all browsers (Mozilla, Netscape, and Konqueror).

[K.C. Chan]

All,
here's what I got when trying, "telnet www.sun.com 80":
trying 192.18.97.241....
telnet: unable to connect to remote host: connection timed out.

Any idea why kernel 2.4.17 is puking on www.sun.com? Thanks.

[Eric Ladner]

Did you enable firewalling support on the new kernel? (wondering if this is a bad entry in your iptables setup)

Does 'telnet www.yahoo.com 80' work as expected also?

Do you have the .config file for your old kernel build? If so, do a diff between the old .config and the new .config and see what modules are missing.

This isn't a routing or java issue since not even the telnet works.

Have you been blacklisted by sun? (haha.. only kidding).

[K.C. Chan]

No, firewall is not enable.
No, I've haven't been denied by Sun, since I'm able to access it with previous kernel
No, I don't have the .config.old file saved.

I guess my only options is to recompile the kernel and pay very close attention to the netowrking part.

[K.C. Chan]

one more thing, when telneting it's getting stock at SYN_SEN state. Does anyone have any idea?

[Ron Kinner]

SYN-SEN just means it started the TCP/IP 3-way handshake but never got a reply.

Ron

[K.C. Chan]

All, thanks for replying. I am now able to access www.sun.com after recompiling the kernel serveral times with each iteration, I modified the networking options of the kernel.

[Eric Ladner]

One more thing before we put this to bed.

Could you do an /sbin/ifconfig eth0 and post the results? I have a suspision about the true nature of your problem.

[K.C. Chan]

here's the output of ifconfig eth0: "eth0 Link encap:Ethernet HWaddr 00:A0:CC:53:6D:A7
inet addr:63.xx.xx.xx Bcast:63.xx.xx255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:19464 errors:0 dropped:0 overruns:0 frame:2
TX packets:8086 errors:6 dropped:0 overruns:1 carrier:5
collisions:0 txqueuelen:100
Interrupt:15 Base address:0x4000"

I've mask my ip with xx, don't want any one probing it. When pinging www.sun.com, it just sits there forever ..... But nslookup was able to resolve www.sun.com. Any idea? I am thinking I missing something that sun's specific at the protocol level. What do you think?

[K.C. Chan]

I've also, taken the liberty of attaching my .config file for all to browse, let me know if I am missing a certain protolcol modules that may lead to this problem. Thanks.

[Ron Kinner]

Michael,

I have recently had a similar problem where my browser refused to go to the forum but would go anywhere else. Turned out there was some garbage in the cookie file. Wiped the cookie file and that fixed the problem. Thanks to the Forum manager Dan for the tip.

Ron

[Charles Slivkoff]

Check for TCP Explicit Congestion Notification:

cat /proc/sys/net/ipv4/tcp_ecn

If this is "1", echo a "0" & see if things magically start working.

http://groups.google.com/groups?q=tcp_ecn&hl=en&safe=off&selm=E15d85n-0000By-00%40scambio.kapa&rnum=2

[K.C. Chan]

As you can see from the kernel config file, tcp_ecn is not set:
"#
# Networking options
#
CONFIG_PACKET=y
# CONFIG_PACKET_MMAP is not set
# CONFIG_NETLINK is not set
# CONFIG_NETFILTER is not set
# CONFIG_FILTER is not set
CONFIG_UNIX=y
CONFIG_INET=y
CONFIG_IP_MULTICAST=y
# CONFIG_IP_ADVANCED_ROUTER is not set
# CONFIG_IP_PNP is not set
# CONFIG_NET_IPIP is not set
# CONFIG_NET_IPGRE is not set
# CONFIG_IP_MROUTE is not set
# CONFIG_INET_ECN is not set
# CONFIG_SYN_COOKIES is not set
# CONFIG_IPX is not set
# CONFIG_ATALK is not set
# CONFIG_DECNET is not set
# CONFIG_BRIDGE is not set
" Can someone tell me what's missing that's causing this network issue. Thanks.