1,191 reputation
57
bio website
location Albany, NY
age 37
visits member for 3 years, 11 months
seen 2 days ago

Just your standard geek. Part programmer, part network wonk..


Jan
28
comment Our exchange server is sending out a lot of spam
look at the bounces, and look at the auth log, If you allow Auth, it is quite possible one of your users has had their Auth Credentials stolen, and being abused. Or it could be that you are getting tons of incoming to invalid recipients. and exchange is accepting and the bouncing to the envelope sender so you are a blowback source. looking at the DSN might help
Jan
2
comment Can't stop DDOS
So basically time to find a new provider. The hardware firewall will not help. 100%, If you have a 1gb/s connection, all that will do is push the attack to the firewall, and fill that pipe. block 53, and maybe ride it out?
Dec
23
comment Apache2 server stops responding
when it stops responding, do a netstat -an | grep 80 and see if you have tons of requests. I'm wondering if is just drawing enough traffic / or an attack that is starving it of resources, since you say the process is still running (just not answering requests)
Dec
12
comment Mail Service requires reboot every few days
Look in the logs and see why the sasl service is failing. how is postfix configured, are you running a separate auth service (Such as cyrus-sasl). Try restarting that service and see if the problem clears. My guess is a dependent service is failing hence the reason restarting mail server doesn't fix it , but reboot does
Nov
22
comment How to check what emails Postfix send at certain date?
just grep the logs for the user's email address?
Nov
13
comment Cannot connect to remote port 465
have you contacted the vps provider? my guess is they they have a filter blocking all sorts of outbound smtp? Are 25 and 587 blocked outbound. Try installing tcptraceroute and tcptraceroute to port 465 and see where it dies.
Nov
8
comment Can't connect to FTP server from a specific location
I've seen Netgears do odd things like this plenty of times. have you tried rebooting it?
Nov
8
comment Can't connect to FTP server from a specific location
what kind of firewall are you going through? can you try from your network but outside the firewall ?
Nov
8
comment Can't connect to FTP server from a specific location
could possible be something with NAT/PAT through the firewall messing up? What kind of firewall?
Nov
7
comment Can a ddos attack stop me from ssh'ing into my server?
but if is is only a couple of IPS that are hitting you, just drop their traffic in iptables on the floor. don't even bother handing it to apache/php way less resources intensive.
Nov
7
comment Can a ddos attack stop me from ssh'ing into my server?
fill the pipe ether direction, peg the cpu, overflow firewall state table, there are tons of ways the DDOS can stop access to any port on a server. That is mostly the point of them. We've had a box or 2 get spider'd really hard by bots, that ignored everything.. Only way to stop them was to drop their traffic in the firewall (they were not Distributed). If the attack is truly distributed there isn't much you can do with robots.txt or rewrites (depends upon what type of attack it is)
Nov
7
comment Why would some folders be invisible on the command line?
is it only directories called system? Is it in all paths? have you tried a different shell? Could the system possibly be compromised? are you trying as root?
Nov
5
comment I can't connect to mysql on a remote server
try running the command tcptraceroute from the ubuntu box (you might need to install it apt-get install tcptraceroute) like this tcptraceroute ip.of.server 3306. This should show you if there is a firewall blocking your connection on 3306, and if so where it is.
Nov
4
comment trace security hole for culprit random “post” mail files
I am guessing that it probably vulnerable versions of software (Most people tend to upload a copy then never update). The way I normally handle it, is look at the domain in question. if running vulnerable software, or the like, disable it, and tell the owner to fix /update
Nov
4
comment trace security hole for culprit random “post” mail files
are they hitting random domains, the same domain. Do each of the domains that get the file uploaded do them have anything in common (same software installed, ie wordpress, joomla, etc..that could be vulnerable)
Nov
4
comment trace security hole for culprit random “post” mail files
need to look at ftp logs, access logs, etc.. to see where/how the file is being upload to the server.
Nov
4
comment I can't connect to mysql on a remote server
are you 100% sure there are no other firewalls in between? Assuming you can Ssh between the two
Oct
24
comment Ssh without password to Embedded read only device
could also use expect scripting language or something like sshkit in ruby to automate the connecting and retrieval from the device, what lang in current script written in.
Oct
19
comment Does Qmail utilize any of Sendmail's own configuration files?
just curious as to why you need both if your program is just calling sendmail to deliver email the qmail wrapper should work the same way?
Oct
9
comment What determines which of a DHCP Relay Agent's IP addresses are attached to relayed requests?
well the problem with 172.17.5.0/23 is that it isn't a valid subnet, since it would need to fall on a bit boundary 172.17.4.0/23, and 172.17.6.0/23 are both valid /23's Perhaps that is why windows wouldn't let you resize it?