I have a Centos 6.3 server -- alone among all my Ubuntu servers for historical reasons -- with Upstart 0.6.5. I need to update that upstart to at least 1.4, and I'd prefer to do it through yum instead of hand compiling it.
Is a there a yum repo with a newer version I could use to update Upstart from?
I'm writing an nginx configuration that requires a proxy, and I need to original ip address. Nginx's HttpProxyModule's $proxy_add_x_forwarded_for variable seems perfectly adequate for the task, except that my Nginx is behind a load balance that sets not X-Forwarded-For, but X-Cluster-Client-Ip.
Now, one possibility would be using
set X-Forwarded-For $http_x_cluster_client_ip,$proxy_add_x_forwarded_for
but sometimes there are direct accesses to the server, which would leave a leading comma in the header. I thought about using if, but that scenario falls right in the middle of the cases where if is problematic to use.
Note that, because the client might have been proxied, I do want to preserve any data present in the X-Forwarded-For header, if one exists, in addition to passing data from X-Cluster-Client-Ip.
Any alternatives?
I decided to decrease the workload on my mail gateway by moving anti-virus processing to a separate server. I created the server, installed clamav-daemon on it, and tested it by running clamdscan from the mail gateway.
Satisfied, I then changed MailScanner as following:
Virus Scanners = clamd
Clamd Port = 3310
Clamd Socket = clamd server's IP address
I restarted mailscanner, and got the following result:
MailScanner[45946]: Clamd::ERROR:: UNKNOWN CLAMD RETURN ./lstat() failed: No such file or directory. ERROR :: /var/spool/MailScanner/incoming/45946
Obviously, MailScanner is not sending the file to be scanned. Instead, it is just telling it to scan a file which, obviously, does not exist on clamd's server.
I find it difficult to believe using clamd in this manner with mailscanner is not possible at all. Rather, I suspect I'm missing something. So... is it possible? If so, what configuration am I missing?
I set up a separate host for clamd to handle virus-scanning, and I want to test it before putting it in production. Now, while MailScanner's configuration for remote clamd is clear and simple, I can't find any information on how to do that with clamdscan. Does anyone know?
I need to log authentication failure on OpenLDAP. What is the proper log level bit for that? Or is there another configuration for such a thing?
Is there any equivalent in Windows to Unix Shell's "exec"? Basically, I need to avoid forking a new process, so that input/output pipes are preserved, as well as process id.
Edit:
So, here's my problem. I have a process A that starts a script, and this script ends by executing a process B. I need for A to get all of B's output, as well as be able to kill B by killing the process it has spawned (the script).
On Unix, executing B with exec does that job.
By default, Debian and Ubuntu (at least) set /etc/ssh/ssh_known_hosts without read permission for others. What's the logic behind that? I can't think of any security risks with o+r, and, on the other hand, having it publicly readable is useful for admin-distributed files.
I'm configuring a Debian Squeeze server to receive syslog from some appliances, but rsyslog is refusing to listen to UDP 514.
The closest I have been able to get from it is to make it listen to TCP 514 with -c2 -r -t514. I haven't found any combination of parameters that got it listening on UDP.
Squeeze's rsyslog version is 4.6.4-2.
Is there a way to change the moderation flag of a member of a list from the command line, with Mailman?
I'd like to know which hosts make a specific DNS query, and at what times. Is there any way to get logs this specific on Bind 9?
For example, I might want to log all A queries for xyzzy.net.
I'm trying to automate the creation of a user for database backup on Postgresql. What grants are required to run pg_dump?
I need to install exim4 through puppet. Because this installation requires interactive configuration, I need a response file, but I don't know how to generate one. So, how do I generate a response file?
I added a second interface to a virtual host by mistake, and now I want to remove it. I couldn't find a command to do it, though. How do I accomplish that?
My outer SMTP is blocking some e-mails with the error 450 4.7.1 Client host rejected: cannot find your hostname, which we traced back to the reject_unknown_client_hostname. As it happens, the hostname to which the reverse address resolves does not, itself, have a DNS record. The chances of getting this fixed are low, but we do need to get their e-mail.
So, can we configure some sort of exception to get around this rule just for them?
I'm doing some sanity checking on an LDAP database in preparation for a version upgrade on our LDAP server, and I came upon a very few users sharing the same sambaSID attribute. I wonder if I should be concerned about it? And, if yes, what would be the easiest way to solve the problem?
I'm trying to figure out why a package was not upgraded unattended, and I have turned my eyes to the Allowed-Origins configuration. However, I do not know how to check the origin and archive of packages in the apt cache. How do I do so?
I have a Debian 2.6.26-2-xen-amd64 system which takes 5 seconds between the second and third failed reverse DNS lookup. All (most?) other similar systems here do the three lookups with little wait between them.
I have tried to figure out what might be causing the difference, but, so far, I have been unable to do so. What might it be?
EDIT
Though I have observed the problem when logging to the machine with sshd, knowing slowness there is usually a problem with reverse dns, I have tested it using host. This is being provided by the package host, version 20000331-9.
Here's the tcpdump output of the test on two machines.
Host with delay:
11:47:58.883885 IP 192.168.20.127.48797 > 172.16.1.1.53: 13275+ PTR? 30.4.16.172.in-addr.arpa. (42)
11:47:58.884258 IP 172.16.1.1.53 > 192.168.20.127.48797: 13275 ServFail 0/0/0 (42)
11:47:58.884326 IP 192.168.20.127.34876 > 172.16.1.1.53: 13275+ PTR? 30.4.16.172.in-addr.arpa. (42)
11:47:58.884804 IP 172.16.1.1.53 > 192.168.20.127.34876: 13275 ServFail 0/0/0 (42)
11:48:03.892639 IP 192.168.20.127.43032 > 172.16.1.1.53: 21337+ PTR? 30.4.16.172.in-addr.arpa. (42)
11:48:03.893282 IP 172.16.1.1.53 > 192.168.20.127.43032: 21337 ServFail 0/0/0 (42)
Host without delay:
11:15:58.222147 IP 192.168.21.26.50046 > 172.16.1.1.53: 2040+ PTR? 30.4.16.172.in-addr.arpa. (42)
11:15:58.222611 IP 172.16.1.1.53 > 192.168.21.26.50046: 2040 ServFail 0/0/0 (42)
11:15:58.222718 IP 192.168.21.26.51288 > 172.16.1.1.53: 2040+ PTR? 30.4.16.172.in-addr.arpa. (42)
11:15:58.223102 IP 172.16.1.1.53 > 192.168.21.26.51288: 2040 ServFail 0/0/0 (42)
11:15:58.223197 IP 192.168.21.26.36545 > 172.16.1.1.53: 20425+ PTR? 30.4.16.172.in-addr.arpa. (42)
11:15:58.223550 IP 172.16.1.1.53 > 192.168.21.26.36545: 20425 ServFail 0/0/0 (42)
I'm using the ganeti2 package on Debian 5. Instance creation goes pretty smoothly, except that it doesn't configure a swap disk automatically, and I'd like it to do so.
Googling around, I found absolutely no one with my problem, which makes me suspect a fundamental mistake on my part, but I can't figure out what. The Ganeti 2 documentation also doesn't touch the subject, though previous versions had an instance creation parameter for that.
So, how can I do it? Or what am I doing wrong?
I need to check the MD5 of a few files on Windows. Any recommendations on either a command line or an explorer-plugin utility?
Years of sysadmin left syslog's severity levels, as described by The BSD Syslog Protocol, clearly imprinted in my mind. You know the drill: Emergency, Alert, Critical, Error, Warning, Notice, Informational and Debug. This left traces elsewhere, such as Java's logger with its Severe, Warning, Info, Config, Fine/r/st.
While discussing it with someone under the impression that Java's was a quick hack, a bad fit, and telling of the mindset, I wondered how old this actually is -- syslog's dating back to the 80s with Sendmail. A quick search reveals that REXX has Termination, Severe, Error, Warning, Informational & Response, which seems to confirm my suspicions.
I'm sure it has its origins in the real world, probably with an army or train company's procedures, and it would be interesting to hear about it, but I'd very much like to know the origin and lineage of severity levels, and the notion of filtering "up to" that comes with it, in the computer business.