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Questions tagged [block]

The tag has no usage guidance.

2
votes
1answer
49 views

IP blocking with .htaccess in Apache 2.4 - Not Working

I want to block specific IP addresses but allow all others. I'm still struggling with this. First I modified the apache2.conf file to look like this: <Directory /var/www/> Options Indexes ...
-5
votes
2answers
45 views

Router's Parental Controls Really Block All Internet Traffics?

I am using Asus 4G-AC53U router. When I turn ON "Parental Controls" to block a client's Internet access, does the router really block ALL kinds of Internet traffics including system's service (such as ...
0
votes
1answer
28 views

Emails go to spam folder on email server with MS Exchange

Emails from redwerk.com email server goes in spam folder on server with MS Exchange. I had performed all kinds of server checkings (SPF, DKIM, Blacklists). Had performed checkings on https://...
0
votes
0answers
681 views

Pfsense block only the internet on one single IP

Im after blocking a single IP on pfsense from the internet only, it can talk to other Ips on the lan fine only the internet. the IP in question is 10.0.0.22 Ive added a rule which failed to work ...
0
votes
2answers
702 views

Performance of iptables

I would like to ask you what is performance of iptables. Let's say that I whitelist and blacklist some IP addresses, I block about 10 000+ IP addresses, so every IP is like new rule. I don't know ...
-1
votes
2answers
61 views

Block a computer from all but 1 or 2 websites?

I'm setting up a computer for our machine shop that is intended for them to only get to a couple sites they may need while working. It needs to still be on our network so they can look at files saved ...
2
votes
1answer
2k views

“Require not ip” .htaccess doesn't work in a single ip

I am having trouble with blocking an IP in .htaccess I've put Require not ip 192.168.20.218 It works, but it blocks the entire network instead of blocking a single IP. Can somebody solve this ...
2
votes
2answers
739 views

How do I unmount one of two devices mounted to the same mount point?

I accidentally left two different devices mounted on /opt: /dev/xvdf on /opt type ext4 (rw,relatime,seclabel,data=ordered) /dev/md0 on /opt type ext4 (rw,relatime,seclabel,stripe=256,data=ordered) ...
1
vote
1answer
139 views

Deciphering kpartx output

I hope I've posted this in the proper place, if I haven't then please advise me on where to move the post. I've tried deciphering the kpartx output myself but now I'm sort of stuck and in need of ...
1
vote
1answer
51 views

Block Clients based on RTT

I am running an application on my Debian server, which uses IPv4 and UDP for data communication. I would like to block every client for a short while, that has a Round Trip Time above 140ms. ...
0
votes
0answers
100 views

Dealing with big blocklists: Is it better to DNS Blackhole or block at firewall level

Setting up some new protections for networks and I've found myself with two different options. Due to the size of the lists (easily 2,500,000+ domains) is it better to setup DNS servers to blackhole ...
1
vote
5answers
273 views

How do you mitigate LAN clients from participating in DDOS?

Most references I've read about mitigating DDOS involve edge routers. However, is there anything you can do to mitigate your LAN clients from unknowlingly participating in a DDOS ? Like blocking ...
0
votes
1answer
2k views

How can I block all HEAD requests to urls that contain a substring on Apache?

A server I administer is being pounded with a poorly coded AWS-built bot that switches IPs constantly and appears to be stuck in a recursive encoding loop. The only consistent fingerprint I can see is ...
1
vote
1answer
977 views

How to block a small IP range in csf

I'm looking for a way to block a small ip range in csf, e.g. 151.80.31.103 to 151.80.31.115 I know how to block each ip by issuing a cmmand csf -d IP, but it is a lot more effective to have a way to ...
-1
votes
2answers
104 views

How to block access to web-hosting servers?

Is there a way to block all web-hosting servers trying to access my server? There are a lot of hacked websites used to do damage to my server and only common thing is IP of agressor (many of IP's) is ...
-3
votes
1answer
254 views

How to prevent an openly recursive DNS server from being abused for DNS amplification [closed]

I have a business need to provide an open and recursive DNS. This DNS has of course been heavily abused by DNS amplification attacks, resulting in 5-10 Mbps sustained outbound load only caused by ...
-1
votes
2answers
334 views

Does the bash usleep block? Or will it yield to other threads? [closed]

I understand there is a usleep command in bash. Is this a "busy" or "blocking" sleep? Or will this yield time to other processes?
0
votes
0answers
221 views

domain redirect to STRATO.NL managed server (block?)

I have a managed server from strato.nl I have a domain on OVH and I want for my OVH domain to redirect to the managed server. I have configured the DNS so that xxx.ovh domains points to the IP of the ...
0
votes
1answer
185 views

Postfix Virtual Domain - mail is send by second server [duplicate]

i setup postfix on a VPS with two domains (each one with own ip) domain1 - 194.xxx.xxx.1 domain2 - 194.xxx.xxx.2 when i send a mail via domain2 - i am getting dmarc reports that the mail uses the ...
1
vote
2answers
924 views

Block direct IP connections to Apache web server [duplicate]

I need to figure out how to block direct IP access to my website. Example: I want it so that when people type my IP address 1.2.3.4 into the browser it doesn't work, but when they type www.example....
0
votes
0answers
207 views

Allow FTP access by a single IP. Restrict all other

I'm using Amazon EC2 Ubuntu instance and want to block all IP except a single IP. So outside my network no one can connect with FTP. I've already tried with following. in vsftpd.conf tcp_wrappers=...
0
votes
1answer
890 views

Block request to certain url call from server

i have website running , that call url of some other website is there any way to block call to particular website. For eg : inside some part of my website a call is made to url like abc.com/xxx/aa ...
1
vote
0answers
497 views

Linux swapping blocks system (freeze)

I have a problem with my Debian Servers. We run 4 different server which all have Intel CPUs and 128GB of RAM. Two of them run Wheezy, two of them run Jessie. We run a Java software on those systems ...
0
votes
1answer
38 views

Avaya switch - need to block port 25

Situation: In QA-DEV Lab environment I need to block port 25 for the egress traffic on AVAYA ERS5510-48T switch. Question: How do I do it using EDM aka Web Interface? Couldn't find anything in ...
0
votes
0answers
217 views

How to block device trying to connect to your wifi

In my log-file I see that hostapd shows that a device is continuously trying to connect and disconnect which slows down the network & pollutes the log-file and. Anyone knows how to block a device ...
0
votes
1answer
5k views

block DNS Amplification Attack by iptables

Last time I've got warings about DNS Amplification Attack from NFOservers.com DDoS notifier 2015-12-30 23:28:52.609178 IP (tos 0x0, ttl 54, id 42635, offset 0, flags [+], proto UDP (17), length 1500)...
2
votes
1answer
236 views

How can I mitigate spoofed emails entering my network?

My company is receiving a lot of spoofed emails. For example. user@mycompany.com receives emails from user@mycompany.com containing malware or a bad links. My domain mycompany.com has a SPF record ...
0
votes
0answers
158 views

server 2012 not receiving data on specific port

I installed a windows server 2012 r2 standard + sql 2008 r2 standard on a new dell server for a client of mine as regular workgroup file server (not acting as a Domain Controller) 3 months ago and all ...
0
votes
0answers
177 views

Xen bridge - block traffic from port range - iptables / ebtables

I use Xen with bridge interface : - eth0 - viifbr0 - Name of VM interface : vifv10XX.0 Do you know if it is possible to block output traffic from source port range for a domU please ? If yes, can ...
1
vote
1answer
217 views

iptables accept specific packet id

I want to allow only packets with a specific id (identification field), for example packets with id=3 are accepted and others dropped. And I want to do the same thing with the offset, so for example ...
2
votes
3answers
188 views

Block people searching for server admin pages

Occasionally I flip through our (apache) access log and I often come across people trying to fish for admin pages. For example, they are trying to access pages like: /wp-login.php /administrator/...
0
votes
1answer
1k views

Iptables drop outgoing HTTPs GET request matches string in payload [closed]

I'm using CentOS 5.8(final), kernel 2.6.18-308.8.2, iptables v1.3.5 I want to block a HTTPs POST/GET request to outside which matches a string (defined as ABCxyz) in the POST/GET payload. I tried to ...
-8
votes
1answer
5k views

MySQL : How to lock all write in all databases? [closed]

I need to block all writes (insert , update, delete) on all databases. How can I do that ? Put all database in Read Only for a period time.
0
votes
1answer
348 views

How i can block requests for a specific page?

I would like to completely delete or block access to a specific page in my site. More specifically, I have seen this exploit "Joomla COM_MEDIA Exploit" : http://all1gat0r.blogspot.gr/2013/08/joomla-...
-3
votes
1answer
61 views

Hosts file to block a website [closed]

I have seen a blog saying that we can block some websites using our hosts file. I have tried the same (shown below), but failed. Entry added in host file as below: 127.0.0.1 www.google.com I ...
0
votes
3answers
751 views

CentOS/Linux Block External Port

Suppose I have an internal service running on port 7676, how would I (On CentOS) block port 7676 from external sources, so that it can only be accessed locally - AKA 127.0.0.1, not using, for example, ...
2
votes
1answer
2k views

PF: Block all, but one subnet firewall rule?

I'm trying to do something that I thought would be relatively simple: Block all the traffic to a test server, other than my company's subnet. I've tried things along these lines (111.111.0.0 is my ...
-1
votes
2answers
787 views

linux minimal block size [closed]

Question : I would like to know if one could create an empty partition with a very small block size, say 100 bytes, and get their experience on the long run. Are there any gotchas ? Context : I ...
-1
votes
1answer
1k views

How to block magnet links using Squid WEB proxy

I have Squid filtering all my WEB traffic running on port 80, I managed to block all torrent links using this ACL acl mediapr urlpath_regex \.torrent$ but I am not able to block magnet links.
2
votes
2answers
16k views

Linux iptables drop traffic based on mac address

I'm doing some testing on my linux VM with one nic, I want to use it as some kind of a firewall which can block traffic of some clients based on a mac address. The client itself is having the VM as a ...
1
vote
1answer
237 views

Debian 7.2 (wheezy) - Block domain

0 down vote favorite A few days ago I figured out that someone was trying to get access to my mailserver, obviously to send spam emails through. After some research I found out that the sender uses ...
0
votes
1answer
80 views

Blocking an IP that is constantly accessing our website

Yesterday I noticed in our apache logs that there is someone constantly accessing our website, sometimes 5 times a second or so, and sometimes once in 5 seconds. However, it's happening 24 hours a day....
9
votes
1answer
1k views

Which block sizes for millions of small files

I have 2x 4TB Disks in hardware RAID1 (it might be a LSI MegaRaid) on Debian Wheezy. The physical block size is 4kB. I'm going to store 150-200 million of small files (between 3 and 10kB). I'm not ...
11
votes
1answer
416 views

how to do I/O sniffing

For sizing purposes I need to understand what requirements an application has to the I/O subsystem. I would love to do what I call I/O sniffing and obtain a list of events from the block layer like ...
0
votes
1answer
103 views

Linux block access to router login page

I am running virtual machines with Gnome desktops on Debian Squeeze and Wheezy. The virtual machines are on a different subnet than the host. I would like to block the virtual machines from ...
2
votes
1answer
1k views

iptables to block VPN-traffic if not through tun0

I have a dedicated Webserver running Debian 6 and some Apache, Tomcat, Asterisk and Mail-stuff. Now we needed to add VPN support for a special program. We installed OpenVPN and registered with a VPN ...
0
votes
1answer
2k views

DNSMasq wildcard top level domain/suffix

I'm running DD-WRT on my router and I need to block certain websites and all their potential suffixes, is that possible or would I have to list them all out individually? What I have is this address=...
-1
votes
2answers
472 views

How do I block visitors by varnish on centos, using nginx as backend?

I want to block visitors from some country, by country code, not by maintain a lot of ip ranges. I can do it using only nginx, but i've just configured varnish to frontend, and I have not found any ...
2
votes
0answers
290 views

Partition block size different from device's and stacked LVM volumes ones

I have a pair of HP ML350 G6 servers with LSI MegaRAID 9266-4i+CacheVault driving Supermicro CSE836E16 enclosures via SAS bracket, filled with WD RE 3TB SATA drives. On these are configured a RAID10 ...
-5
votes
1answer
3k views

iptables block access to port 53 [closed]

I would like to block access to any DNS server (port 53) except for my own $DNS_IP1, $DNS_IP2. $DNS_IP1, $DNS_IP2 are not part of my IP range but are out IPs.