Zabbix: Really frustrating me now

I wrote about Zabbix Installation for Layman sometimes back and really recommended itzabbix1_thumb_thumb for all system administrators out there, due to its simplicity, flexibility and promising nature about lots of aspects.

But now days, look like myself in deep troubles with the same. I am getting strange kind of problems with well established setups of Zabbix, when no one has altered any kind of configuration that is really very very strange. May be my knowledge about this product is lesser; may be reason is just that I am unable to find any proper book over it; may be the manual itself is one of worse, one could come across. Reason might be any of them or all of them, but its getting really unstable for me. It works perfectly after installation for sometime, but gets unstable soon as data grows. I am just finding one different thing in my environment that our servers run 9 AM-9PM, not 24 hours, but this should be the reason for any standard product. Or it might be something happened behind my back, when I was on leave for 3-4 days. Whatever the reasons might be, I am not able to trace it until now.


Listing here some of the issues I am facing with it, which are yet unexplained/ unresolved:



Problem 1: High Dependency on Local Time :- The first problem, I faced with Zabbix was, its going completely out of tune if somehow local time of the server get altered by any means. I tried even network time, but just of no use. You are left to pray about this only. Its been an issue since long and I have seen warnings about it manuals and books.

I really think that it should have been fixed till now (means some kind of automatic handling or making server time synced with clients etc). If you were offering this solution to corporate as along this ‘bug’ makes it completely unreliable.


Problem 2: Broken graphs later on as Data increases :- I am really not sure about this problem, but its making me low on confidence in front of management about this product. I am getting really many strange scenarios with it. The biggest Zabbix Server of mine was taking care of around 25-30 servers and this was going awry again and again. Like I am getting data in latest data tab correctly, I am getting data in 4 hours and 8 hours graphs correctly, but getting no graphs in 1 hour and 2 hours graphs, while its showing data but no lines on graph.

Searching through forums say that it might due to much data in MySQL tables and MySQL might be needed to be retuned. But I don’t think that such an application would not be able to handle a mere 2 dozen servers for even straight 7 days. No disk space issue (100 GB free), No Memory Issue (1 GB RAM), processor is Core 2 Duo, have enabled house cleanup, have increased the memory limits, but still….


Problem 3: No support as I am unable to find any person, who knows this software a bit more. Look like most of the people using more worse NagiOS only. Professionals require contract for support and forums are not that useful as its not a simple piece of application and problems are of diverse nature… literally too many. Logs are confusing and most of the time not that much info even on setting it on debug mode.



My aim of this post is not to criticize Zabbix itself here, but its support is really poor and many things not that explained in forums and manuals. Much hard to find anyone, who knows it through.

Currently looking for someone, who might be dealing with Zabbix in his environment and could offer help out of the way. I want to invite all who know a thing or two about Zabbix to share the knowledge with me and same will be with myself.

photo of Nitish KumarNitish Kumar

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Squid Proxy Server: Step by Step Dummies Manual

As promised to myself, I have updated Squid Proxy Server Implementation Manual with use cases and recommendations. Also, the related two articles has been removed and merged into the single link for avoiding ambiguity.

This also involves basic firewall and normal issues/ requirements like Outlook etc. I hope, it would be helpful for many people out there. Post your opinions and suggestions for sure.

Google Vs China, Strategy or Real Concerns?

It seems that like the last year went, Google still keeping itself well in news.

| Got to read one tweet @ claymillThe Google /China incident feels ominously profound; it’s an ending and a beginning but nobody knows exactly what ended or began.” |


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Google; A name always found in support of Open Internet and even recently made a precise statement over definition of Open and has a philosophy that believe that “open systems win”. They lead to more innovation, value, and freedom of choice for consumers, and a vibrant, profitable, and competitive ecosystem for businesses. china

China; A nation, who leads in methods of censorship. Internet censorship in China is conducted under a wide variety of laws and administrative regulations. In accordance with these laws, more than sixty Internet regulations have been made by the People’s Republic of China (PRC) government, and censorship systems are vigorously implemented by provincial branches of state-owned ISPs, business companies, and organizations.


Internet Censorship and Google: The History

google-chinaFor the first time, Google found to have started to censor its search results in 2002 in compliance with United States’ DMCA legislation. Although even in that time, this move was taken in innovative ways as banned results were replaced by corresponding DMCA complaint. Later on the similar phenomenon was noticed with other countries like United Kingdom (Since September 2006), Germany & France (Since October 2002) and most importantly with China (Since December 2005) in adherence with their corresponding country policies.

With China, Google’s journey been with troubles since the beginning due to huge difference in philosophy. In fact, there was a time when popular search engines such as Altavista, Yahoo!, and Google were completely banned from use in China, although later the ban was lifted, but filtering remained continued.

Google officially announced its adherence with China’s policy in January 2006 and launched a Chinese-language service that will be stripped of content deemed offensive or subversive. Google somehow managed to devise an interesting solution (must read link) for this technically big problem. Later on other Internet giants including Yahoo and Microsoft’s MSN have also censored material "in exchange" for being allowed to tap a market comprising 110 million Internet users, the world’s second-largest market.


An Example of Censorship could be cited as below:

human-rights-china

human-rights-china-china


Amnesty International and Human Rights Watch strongly condemned Google’s compliance with China’s Golden Shield Project, calling it a form of self-censorship. According to Amnesty,

“ These forms of censorships seem to contradict the very principles that Google — whose unofficial motto is "don’t be evil" — was founded upon. Until January 2006, Google’s Support Center claimed that it "does not censor results for any search term", but removed this claim after reaching its deal with China. ”


By 12th January 2010, Google finally decided to stand against China’s Censorship

The sensational news was uncovered by Google itself by their blog post on 12th January 2010, in which they wrote that they faced a sophisticated attack in mid Dec 2009, where the hackers targeted Google’s corporate infrastructure originating from China that resulted in the theft of intellectual property from Google. Google claimed that a primary goal of the attackers was accessing the Gmail accounts of Chinese human rights activists.

Google said

We launched Google.cn in January 2006 in the belief that the benefits of increased access to information for people in China and a more open Internet outweighed our discomfort in agreeing to censor some results. At the time we made clear that "we will carefully monitor conditions in China, including new laws and other restrictions on our services. If we determine that we are unable to achieve the objectives outlined we will not hesitate to reconsider our approach to China."

These attacks and the surveillance they have uncovered–combined with the attempts over the past year to further limit free speech on the web–have led us to conclude that we should review the feasibility of our business operations in China. We have decided we are no longer willing to continue censoring our results on Google.cn, and so over the next few weeks we will be discussing with the Chinese government the basis on which we could operate an unfiltered search engine within the law, if at all. We recognize that this may well mean having to shut down Google.cn, and potentially our offices in China.


After attacks over RockYou and Twitter, this was a news which would have caused a stir among people for security concerns of cloud with headlines like “Now even Google got compromised”, like one tweet @vicsingh said “google has balls for potential china pullout, but the positive externality is that no one is talking about the vulnerability of their cloud”, but the matter went much more twisted and interesting as Google shared this information with the world saying …

“We have taken the unusual step of sharing information about these attacks with a broad audience not just because of the security and human rights implications of what we have unearthed, but also because this information goes to the heart of a much bigger global debate about freedom of speech.”

BoyThinking More interesting were their next two decisions;

  1. One was a somewhat not that noticed move by Google after around 6 hours of their blog post about attacks, where they made their Gmail and other services using https access by default.
  2. The other one came with the same blog post itself saying “We have decided we are no longer willing to continue censoring our results on Google.cn”


Why Google suddenly became ready to even leave China?

googlechina5-420x0

As per information revealed by Google itself, the attack was mere phishing attacks “These accounts have not been accessed through any security breach at Google, but most likely via phishing scams or malware placed on the users’ computers.

Now, the million dollars question to be asked is, such attacks been common to whole community of internet users and all leading companies since decades and Google itself said (if true) that only two of the accounts were compromised up to an extent (not even completely) then what became the reason of this huge decision, which could impact many things all around the globe in many ways?


questionIts true that for years, Google faced withering criticism for what activists and lawmakers said was a willingness to abandon social responsibility in return for greater wealth. Its true that Google co-founder Sergey Brin shared many of the critics’ concerns about Google’s presence in China (but he publicly maintained that even a censored version of the company’s search engine was better than none at all). Its also true that recent move invited world wide praises for Google.

But still it will be a question to ask that why now after four years? Is the biggest market (around 20% of whole world) became less lucrative suddenly for which many compromises were made? Is performance troubles due to excessive filtering seems to nail down Google’s cloud strategies?

Note that even now  Google is filtering its search results and its operation in China is under a review as per Google itself, not opted out. Google officials said that they will be discussing with the Chinese government the basis on which they could operate an unfiltered search engine within the law, if at all. So, wait and watch.


This link sites Testimony of Google Inc. about China from their blog post in 2006. Have a read. I would also like to invite you all to comment upon what you think about this news.

Zabbix Server: Some issues and some tips

In addition to the implementation details, I wrote few days back, I would like the add up some precautions and resolution to some issues, which would sure make life with Zabbix little easier for newbie .


Keep the date time configuration correct: I really faced much trouble over this one. Before installation of any new server, make sure that you have chosen correct Timezone settings. For most of the version of Linux, you need to type setup on console and then go to timezone configuration and set as per yours (e.g. Asia/Kolkata) and then make the same entry in /etc/php.ini for variable date.timezone as well (e.g. data.timezone=Asia/Kolkata).

This is really an irritating bug at Zabbix side as client and server both the sides should use Server Timezone entry. But its not resolved till now and might be reason for trouble to many.

Problem I faced with it: I went really a lot of trouble with time settings with one of my zabbix servers. While all others were working fine, one was not giving any data on graphs. Although resolution worked in some other way, but I would like to give a few basics —

1. Verify all the settings like agents are referencing the right server or not

2. Check that whether ports are open or not.

The Server listens on 10051 and client listens on 10050. Now, How to Check open Ports in Linux? Although there are many ways to do the same, but simpler is using netstat

# netstat –ntulp

It will show all open ports and also that which process is using them. You must find 10051 port opened on Server.

3. Check the latest data under monitoring tab (My case) This provides you info about clients that when you last moment received data from them and what data. In my case, I found that my clients received data in future time that’s why there was nothing on the graph as it was checking data in past time.

I struggled a lot, but found only one solution that was to delete all the clients from Zabbix and then import the same configuration again. When you delete one host, then it delete all the logs related to it and that’s why when you re-import the configuration then it will start-a-fresh. Thats why I insist on making a backup of all configuration once, coz after then for recreating whole thing, you need just an import and then recreating screens. 🙂


Increase the upload size in php.ini: For using the above feature, its a necessary step as  many times the size of xml file might exceed the default 2mb. Find the maximum_upload_size and increase to be at least 8mb from 2mb (default).


Copying Configuration is better in place of creating new: For Linux Servers, copy all the  configurations/ items/ graphs etc from the Linux Based Zabbix Server itself, while for Windows, you need to configure one first and then copying all the entry to other in similar manner as was in Linux Servers.


Replace CPU Utilization Screen with Memory Utilization: Although it depends on your requirements, but for me in general, its better to replace CPU Utilization screen with a custom made Memory Utilization screen made of items Total Memory and Free Memory as CPU Load data is sufficient to monitor CPU Health in most of the cases.


Make a configuration backup once you are done with adding your servers: This is the most important thing as it helps you out in quickly restoring the things, if want to migrate the whole thing to new server in case of any problem in original server. You need to use Export feature of existing server to export a xml file (might be >2 mb) and then import it once you done with installing a fresh server or existing server. Then you will be needed to change the Server IP in all client’s zabbix agent configurations (/etc/zabbix/zabbix_agentd.conf in Linux and c:\program files\zabbix agent\zabbix_agentd.conf in windows) and restarted their zabbix services.

Create a slideshow for all the servers: This is a feature, which makes it look more cool. Create a slideshow of all the screens, you create and it will keep it changing in specified time duration (default is 5 secs), which is quite better, comfortable and effective than changing the screens yourself to take a look. You could make very good use of a projector with this feature 😉